id int64 0 18.9k | biography stringlengths 151 1.51k | qa listlengths 1 25 |
|---|---|---|
16,307 | Poland has historically been staunchly pro-American, dating back to General Tadeusz Kościuszko and Casimir Pulaski's involvement in the American Revolution. This pro-American stance was reinforced following favorable American intervention in World War I (leading to the creation of an independent Poland) and the Cold Wa... | [
{
"answer": "staunchly pro-American",
"question": "What had been Poland's stance towards the US, historically?"
},
{
"answer": "favorable American intervention in World War I",
"question": "What led to the creation of an independent Poland?"
},
{
"answer": "a large force",
"question"... |
16,308 | The Party of Reconstruction in Sicily, which claimed 40,000 members in 1944, campaigned for Sicily to be admitted as a U.S. state. This party was one of several Sicilian separatist movements active after the downfall of Italian Fascism. Sicilians felt neglected or underrepresented by the Italian government after the an... | [
{
"answer": "40,000 members",
"question": "How many members did the Party of Reconstruction in Sicily have in 1944?"
},
{
"answer": "for Sicily to be admitted as a U.S. state",
"question": "What did the Party of Reconstruction in Sicily campaign for?"
},
{
"answer": "1861",
"question... |
16,309 | There are four categories of terra nullius, land that is unclaimed by any state: the small unclaimed territory of Bir Tawil between Egypt and Sudan, Antarctica, the oceans, and celestial bodies such as the Moon or Mars. In the last three of these, international treaties (the Antarctic Treaty, the United Nations Convent... | [
{
"answer": "the small unclaimed territory of Bir Tawil between Egypt and Sudan, Antarctica, the oceans, and celestial bodies",
"question": "What are the four categories of terra nullius?"
},
{
"answer": "the Antarctic Treaty, the United Nations Convention on the Law of the Sea, and the Outer Space ... |
16,310 | An antenna (plural antennae or antennas), or aerial, is an electrical device which converts electric power into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver. In transmission, a radio transmitter supplies an electric current oscillating at radio frequency (i.e. a high freque... | [
{
"answer": "An antenna",
"question": "What device is able to change electric powerinto radio waves and also do the reverse?"
},
{
"answer": "radio transmitter or radio receiver",
"question": "What device is often used in conjuntion with the antenna?"
},
{
"answer": "transmission",
"... |
16,311 | Typically an antenna consists of an arrangement of metallic conductors (elements), electrically connected (often through a transmission line) to the receiver or transmitter. An oscillating current of electrons forced through the antenna by a transmitter will create an oscillating magnetic field around the antenna eleme... | [
{
"answer": "transmission line",
"question": "What is frequently used to connect elements to the receiver?"
},
{
"answer": "radiate away",
"question": "During transmission does the electric field wave move closer to the antenna?"
},
{
"answer": "electrons",
"question": "What particle... |
16,312 | The words antenna (plural: antennas in US English, although both "antennas" and "antennae" are used in International English) and aerial are used interchangeably. Occasionally the term "aerial" is used to mean a wire antenna. However, note the important international technical journal, the IEEE Transactions on Antennas... | [
{
"answer": "aerial",
"question": "What is an acceptable synonym for antenna?"
},
{
"answer": "wire antenna",
"question": "What can sometimes be meant by the term aerial specifically?"
},
{
"answer": "antennae",
"question": "What is one way of referring to more than one antenna?"
}... |
16,313 | The origin of the word antenna relative to wireless apparatus is attributed to Italian radio pioneer Guglielmo Marconi. In the summer of 1895, Marconi began testing his wireless system outdoors on his father's estate near Bologna and soon began to experiment with long wire "aerials". Marconi discovered that by raising ... | [
{
"answer": "Guglielmo Marconi",
"question": "Who is most associated with the emergence of the word antenna?"
},
{
"answer": "1895",
"question": "When did experimentation with electromagnetic waves begin?"
},
{
"answer": "raising the \"aerial\" wire",
"question": "What is a way to in... |
16,314 | Antennas are required by any radio receiver or transmitter to couple its electrical connection to the electromagnetic field. Radio waves are electromagnetic waves which carry signals through the air (or through space) at the speed of light with almost no transmission loss. Radio transmitters and receivers are used to c... | [
{
"answer": "Antennas",
"question": "What is essential for the mating of the elements that create radio waves?"
},
{
"answer": "speed of light",
"question": "How fast are signals produced by antenna transmitted?"
},
{
"answer": "mobile telephones",
"question": "What is one system tha... |
16,315 | One example of omnidirectional antennas is the very common vertical antenna or whip antenna consisting of a metal rod (often, but not always, a quarter of a wavelength long). A dipole antenna is similar but consists of two such conductors extending in opposite directions, with a total length that is often, but not alwa... | [
{
"answer": "metal rod",
"question": "What is the main element of an omnidirectional antenna?"
},
{
"answer": "dipole",
"question": "What type of antenna would most likely be a half a wavelength long?"
},
{
"answer": "horizontally",
"question": "In which direction would you expect to... |
16,316 | Both the vertical and dipole antennas are simple in construction and relatively inexpensive. The dipole antenna, which is the basis for most antenna designs, is a balanced component, with equal but opposite voltages and currents applied at its two terminals through a balanced transmission line (or to a coaxial transmis... | [
{
"answer": "relatively inexpensive",
"question": "Are basic antennas expensive?"
},
{
"answer": "dipole antenna",
"question": "What is the foundation most often used when creating new antenna models?"
},
{
"answer": "monopole antenna",
"question": "What category do vertical antennas... |
16,317 | Antennas more complex than the dipole or vertical designs are usually intended to increase the directivity and consequently the gain of the antenna. This can be accomplished in many different ways leading to a plethora of antenna designs. The vast majority of designs are fed with a balanced line (unlike a monopole ante... | [
{
"answer": "gain of the antenna",
"question": "What are different designs aimed at increasing?"
},
{
"answer": "balanced line",
"question": "What is different from a monopole antenna with most other antenna types?"
},
{
"answer": "concentration",
"question": "Gain when referring to ... |
16,318 | For instance, a phased array consists of two or more simple antennas which are connected together through an electrical network. This often involves a number of parallel dipole antennas with a certain spacing. Depending on the relative phase introduced by the network, the same combination of dipole antennas can operate... | [
{
"answer": "two or more",
"question": "How many antenna would make up a phased array?"
},
{
"answer": "relative phase",
"question": "What determines if the antenna creates a broadside array or an end fire array?"
},
{
"answer": "omnidirectional or weakly directional",
"question": "W... |
16,319 | However a log-periodic dipole array consists of a number of dipole elements of different lengths in order to obtain a somewhat directional antenna having an extremely wide bandwidth: these are frequently used for television reception in fringe areas. The dipole antennas composing it are all considered "active elements"... | [
{
"answer": "log-periodic dipole array",
"question": "What type of antenna formation is made up of multiple dipole elements of varying lengths?"
},
{
"answer": "extremely wide bandwidth",
"question": "What is the benefit of this formation type?"
},
{
"answer": "Yagi-Uda Antenna",
"qu... |
16,320 | At low frequencies (such as AM broadcast), arrays of vertical towers are used to achieve directionality and they will occupy large areas of land. For reception, a long Beverage antenna can have significant directivity. For non directional portable use, a short vertical antenna or small loop antenna works well, with th... | [
{
"answer": "vertical",
"question": "For radio broadcast that one would hear in their car what type of towers are used?"
},
{
"answer": "short vertical antenna",
"question": "If one wished to take an antenna to different locations, which type would be best?"
},
{
"answer": "achieve direc... |
16,321 | An antenna lead-in is the transmission line (or feed line) which connects the antenna to a transmitter or receiver. The antenna feed may refer to all components connecting the antenna to the transmitter or receiver, such as an impedance matching network in addition to the transmission line. In a so-called aperture ante... | [
{
"answer": "antenna lead-in",
"question": "What is mainly responsible for the connection of the antenna to its end destinations?"
},
{
"answer": "antenna feed",
"question": "What is the group of elements used to join the elements of an antenna?"
},
{
"answer": "aperture antenna",
"q... |
16,322 | Monopole antennas consist of a single radiating element such as a metal rod, often mounted over a conducting surface, a ground plane. One side of the feedline from the receiver or transmitter is connected to the rod, and the other side to the ground plane, which may be the Earth. The most common form is the quarter-wav... | [
{
"answer": "metal rod",
"question": "Monopole antennas consist of what element?"
},
{
"answer": "nondirectional antennas",
"question": "What are small monopoles used as?"
},
{
"answer": "quarter-wave monopole",
"question": "What the most common form? "
},
{
"answer": "Monopo... |
16,323 | The most widely used class of antenna, a dipole antenna consists of two symmetrical radiators such as metal rods or wires, with one side of the balanced feedline from the transmitter or receiver attached to each. A horizontal dipole radiates in two lobes perpendicular to the antenna's axis. A half-wave dipole the most ... | [
{
"answer": "dipole antenna",
"question": "What is the most widley used antenna class?"
},
{
"answer": "horizontal dipole",
"question": " ... |
16,324 | A necessary condition for the aforementioned reciprocity property is that the materials in the antenna and transmission medium are linear and reciprocal. Reciprocal (or bilateral) means that the material has the same response to an electric current or magnetic field in one direction, as it has to the field or current i... | [
{
"answer": "linear and reciprocal",
"question": "What must be true of the antenna and transmission medium for the repiprocity rule to apply ?"
},
{
"answer": "ferrite",
"question": "What is one material that does not have this quality?"
},
{
"answer": "radar",
"question": "How can t... |
16,325 | Antennas are characterized by a number of performance measures which a user would be concerned with in selecting or designing an antenna for a particular application. Chief among these relate to the directional characteristics (as depicted in the antenna's radiation pattern) and the resulting gain. Even in omnidirectio... | [
{
"answer": "performance measures",
"question": "How could one deide what type of antenna is nedded for a project?"
},
{
"answer": "directional characteristics",
"question": "What would most likely be the main concern in making this decision?"
},
{
"answer": "horizontal directions",
... |
16,326 | Resonant antennas are expected to be used around a particular resonant frequency; an antenna must therefore be built or ordered to match the frequency range of the intended application. A particular antenna design will present a particular feedpoint impedance. While this may affect the choice of an antenna, an antenna'... | [
{
"answer": "Resonant antennas",
"question": "Which antenna type would be best for a project requiring a specific frequency?"
},
{
"answer": "built or ordered",
"question": "How could an antenna be made to coordinate with the needed frequency?"
},
{
"answer": "particular antenna design",... |
16,327 | An antenna transmits and receives radio waves with a particular polarization which can be reoriented by tilting the axis of the antenna in many (but not all) cases. The physical size of an antenna is often a practical issue, particularly at lower frequencies (longer wavelengths). Highly directional antennas need to be ... | [
{
"answer": "polarization",
"question": "What is the essential difference in radio waves transmitted by an antenna?"
},
{
"answer": "tilting the axis",
"question": "How can this be adjusted more easily than changing antenna types?"
},
{
"answer": "at lower frequencies",
"question": "... |
16,328 | The majority of antenna designs are based on the resonance principle. This relies on the behaviour of moving electrons, which reflect off surfaces where the dielectric constant changes, in a fashion similar to the way light reflects when optical properties change. In these designs, the reflective surface is created by ... | [
{
"answer": "electrons",
"question": "What particle's migration does the resonance principle rely on?"
},
{
"answer": "resonance principle",
"question": "What is the basis for the way most antennas are developed?"
},
{
"answer": "reflective",
"question": "What type of surface is form... |
16,329 | The radio signal's electrical component induces a voltage in the conductor. This causes an electrical current to begin flowing in the direction of the signal's instantaneous field. When the resulting current reaches the end of the conductor, it reflects, which is equivalent to a 180 degree change in phase. If the condu... | [
{
"answer": "electrical component",
"question": "What part of the radio signal creates voltage?"
},
{
"answer": "instantaneous field",
"question": "What would the electric current always gravitate to?"
},
{
"answer": "180 degree change in phase",
"question": "What is the outcome when... |
16,330 | The ordinary half-wave dipole is probably the most widely used antenna design. This consists of two 1⁄4-wavelength elements arranged end-to-end, and lying along essentially the same axis (or collinear), each feeding one side of a two-conductor transmission wire. The physical arrangement of the two elements places them ... | [
{
"answer": "half-wave dipole",
"question": "What is the most popular antenna type?"
},
{
"answer": "transmission line",
"question": "What is the current usually beng put into it or pulled out of?"
},
{
"answer": "collinear",
"question": "Elements in a half wave dipole and on an iden... |
16,331 | The standing wave forms with this desired pattern at the design frequency, f0, and antennas are normally designed to be this size. However, feeding that element with 3f0 (whose wavelength is 1⁄3 that of f0) will also lead to a standing wave pattern. Thus, an antenna element is also resonant when its length is 3⁄4 of a ... | [
{
"answer": "f0",
"question": "What frequency are antennas normally designed to be?"
},
{
"answer": "3f0",
"question": "What can be added to f0 to create a standing wave pattern?"
},
{
"answer": "1⁄4",
"question": "What multiple is essential for wavelengths?"
},
{
"answer": "... |
16,332 | The quarter-wave elements imitate a series-resonant electrical element due to the standing wave present along the conductor. At the resonant frequency, the standing wave has a current peak and voltage node (minimum) at the feed. In electrical terms, this means the element has minimum reactance, generating the maximum c... | [
{
"answer": "imitate",
"question": "How do quarter wave elements act in relation to a series relevant electrical element?"
},
{
"answer": "resonant frequency",
"question": "What frequency develops a current peak?"
},
{
"answer": "minimum reactance",
"question": "How would you describ... |
16,333 | It is possible to use the impedance matching concepts to construct vertical antennas substantially shorter than the 1⁄4 wavelength at which the antenna is resonant. By adding an inductance in series with the antenna, a so-called loading coil, the capacitive reactance of this antenna can be cancelled leaving a pure resi... | [
{
"answer": "impedance matching",
"question": "For use with more than one channel changes are made to increase what property?"
},
{
"answer": "inductance",
"question": "What could be coupled with an antenna to form pure resistance?"
},
{
"answer": "transmission line",
"question": "Wh... |
16,334 | The end result is that the resonant antenna will efficiently feed a signal into the transmission line only when the source signal's frequency is close to that of the design frequency of the antenna, or one of the resonant multiples. This makes resonant antenna designs inherently narrowband, and they are most commonly u... | [
{
"answer": "resonant multiples",
"question": " If your were unable to match the source frequency with the design frequency of the antenna what could you use?"
},
{
"answer": "single target signal",
"question": "What is the most common application of resonant antennas?"
},
{
"answer": "r... |
16,335 | The amount of signal received from a distant transmission source is essentially geometric in nature due to the inverse square law, and this leads to the concept of effective area. This measures the performance of an antenna by comparing the amount of power it generates to the amount of power in the original signal, mea... | [
{
"answer": "inverse square law",
"question": "What accounts for the geometry involved in the use of an antenna?"
},
{
"answer": "Watts per square metre",
"question": " How is the compactness of the signal measured?"
},
{
"answer": "higher performance",
"question": "What type of proj... |
16,336 | Returning to the basic concept of current flows in a conductor, consider what happens if a half-wave dipole is not connected to a feed point, but instead shorted out. Electrically this forms a single 1⁄2-wavelength element. But the overall current pattern is the same; the current will be zero at the two ends, and reach... | [
{
"answer": "feed point",
"question": "What is a half wave dipole need to be coupled with in most instances?"
},
{
"answer": "center",
"question": "What part of the current is usually strongest?"
},
{
"answer": "standing wave pattern",
"question": "What does this result in?"
},
{... |
16,337 | A Yagi-Uda array uses passive elements to greatly increase gain. It is built along a support boom that is pointed toward the signal, and thus sees no induced signal and does not contribute to the antenna's operation. The end closer to the source is referred to as the front. Near the rear is a single active element, typ... | [
{
"answer": "Yagi-Uda array",
"question": "What can take advantage of these elements to add more gain?"
},
{
"answer": "does not contribute",
"question": "Does this device improve the operation of the antenna?"
},
{
"answer": "directors",
"question": "What is the name for passive ele... |
16,338 | It is also possible to use multiple active elements and combine them together with transmission lines to produce a similar system where the phases add up to reinforce the output. The antenna array and very similar reflective array antenna consist of multiple elements, often half-wave dipoles, spaced out on a plane and ... | [
{
"answer": "active elements",
"question": "What can be paired with transmission lines to create phases that would support output?"
},
{
"answer": "half-wave dipoles",
"question": "What is the most common element used to create a single in phase signal?"
},
{
"answer": "phase lengths",
... |
16,339 | Reflection of the original signal also occurs when it hits an extended conductive surface, in a fashion similar to a mirror. This effect can also be used to increase signal through the use of a reflector, normally placed behind the active element and spaced so the reflected signal reaches the element in-phase. Generall... | [
{
"answer": "extended conductive surface",
"question": "If you wanted to somehow clone the original signal you could use?"
},
{
"answer": "increase",
"question": "What effect would the use of a reflector have on a signal?"
},
{
"answer": "less than 1⁄10",
"question": "What allowance ... |
16,340 | Another extreme case of impedance matching occurs when using a small loop antenna (usually, but not always, for receiving) at a relatively low frequency where it appears almost as a pure inductor. Resonating such an inductor with a capacitor at the frequency of operation not only cancels the reactance but greatly magni... | [
{
"answer": "a capacitor at the frequency of operation",
"question": "What magnifies the small radiation resistance of a loop?"
},
{
"answer": "small ferrite loop antenna",
"question": "What is resonated by a capacitor along with the receiver tuning that maintains resonance over the AM broadcast... |
16,341 | Antenna tuning generally refers to cancellation of any reactance seen at the antenna terminals, leaving only a resistive impedance which might or might not be exactly the desired impedance (that of the transmission line). Although an antenna may be designed to have a purely resistive feedpoint impedance (such as a dipo... | [
{
"answer": "resistive impedance",
"question": "What is left after antenna tuning?"
},
{
"answer": "antenna terminals",
"question": "Where does cancellation of any reactance seen?"
},
{
"answer": "parallel capacitance",
"question": "What can be used to cancel a inductibe reactance or... |
16,342 | Although a resonant antenna has a purely resistive feed-point impedance at a particular frequency, many (if not most) applications require using an antenna over a range of frequencies. An antenna's bandwidth specifies the range of frequencies over which its performance does not suffer due to a poor impedance match. Als... | [
{
"answer": "resonant",
"question": "What type of antenna has impedance at a specific frequency?"
},
{
"answer": "bandwidth",
"question": "What term can be used to refer to the usable spectrum of an antennas frequency?"
},
{
"answer": "impedance match",
"question": "What causes the f... |
16,343 | Instead, it is often desired to have an antenna whose impedance does not vary so greatly over a certain bandwidth. It turns out that the amount of reactance seen at the terminals of a resonant antenna when the frequency is shifted, say, by 5%, depends very much on the diameter of the conductor used. A long thin wire us... | [
{
"answer": "diameter",
"question": "What characteristic of the conductor changes the amount of reactance?"
},
{
"answer": "reactance",
"question": "What characteristic would be better if it were steady?"
},
{
"answer": "A long thin wire",
"question": "What would be used to create a ... |
16,344 | Rather than just using a thick tube, there are similar techniques used to the same effect such as replacing thin wire elements with cages to simulate a thicker element. This widens the bandwidth of the resonance. On the other hand, amateur radio antennas need to operate over several bands which are widely separated fro... | [
{
"answer": "widens",
"question": "What effect do cages have on the spectrum of usable frequencies?"
},
{
"answer": "cages",
"question": "What type of tubes are generally used for sturdier always of antennas?"
},
{
"answer": "connecting resonant elements",
"question": "How could one ... |
16,345 | Gain is a parameter which measures the degree of directivity of the antenna's radiation pattern. A high-gain antenna will radiate most of its power in a particular direction, while a low-gain antenna will radiate over a wider angle. The antenna gain, or power gain of an antenna is defined as the ratio of the intensity ... | [
{
"answer": "gain",
"question": "What is an acknowledgement of the range of possible direction for and antenna?"
},
{
"answer": "power gain",
"question": "What is another way to refer to an antennas gain?"
},
{
"answer": "power per unit surface area",
"question": "What is the meaning... |
16,346 | High-gain antennas have the advantage of longer range and better signal quality, but must be aimed carefully at the other antenna. An example of a high-gain antenna is a parabolic dish such as a satellite television antenna. Low-gain antennas have shorter range, but the orientation of the antenna is relatively unimport... | [
{
"answer": "longer range",
"question": "Antennas with higher gain have what positive feature?"
},
{
"answer": "amplifier gain",
"question": "What is a measure of how much efficient is improved by adding a device designed to make something stronger?"
},
{
"answer": "parabolic dish",
... |
16,347 | Due to reciprocity (discussed above) the gain of an antenna used for transmitting must be proportional to its effective area when used for receiving. Consider an antenna with no loss, that is, one whose electrical efficiency is 100%. It can be shown that its effective area averaged over all directions must be equal to ... | [
{
"answer": "proportional",
"question": "What must the relationship of an antenna and the receiving area be due to reciprocity?"
},
{
"answer": "no loss",
"question": "what could an antenna with complete electrical efficiency be said to have?"
},
{
"answer": "Aeff",
"question": "Anot... |
16,348 | The radiation pattern of an antenna is a plot of the relative field strength of the radio waves emitted by the antenna at different angles. It is typically represented by a three-dimensional graph, or polar plots of the horizontal and vertical cross sections. The pattern of an ideal isotropic antenna, which radiates eq... | [
{
"answer": "relative field strength",
"question": "A plot of the radiation behaviors of an antenna would show what?"
},
{
"answer": "three-dimensional graph",
"question": "What type of pictoral aid is often used to show this?"
},
{
"answer": "isotropic",
"question": " A sphere shows... |
16,349 | The radiation of many antennas shows a pattern of maxima or "lobes" at various angles, separated by "nulls", angles where the radiation falls to zero. This is because the radio waves emitted by different parts of the antenna typically interfere, causing maxima at angles where the radio waves arrive at distant points in... | [
{
"answer": "nulls",
"question": "What is the term that refers to areas where an antennas radiation is zero? "
},
{
"answer": "interfere",
"question": "What do radio waves do that account for maxima or nulls in an antenna pattern?"
},
{
"answer": "lobe",
"question": "If you desired t... |
16,350 | As an electro-magnetic wave travels through the different parts of the antenna system (radio, feed line, antenna, free space) it may encounter differences in impedance (E/H, V/I, etc.). At each interface, depending on the impedance match, some fraction of the wave's energy will reflect back to the source, forming a sta... | [
{
"answer": "radio",
"question": "What is one piece that makes up an antenna system?"
},
{
"answer": "standing wave",
"question": "What is created by a portion of a radio waves energy reversing?"
},
{
"answer": "standing wave ratio",
"question": "A term that refers to the highs and l... |
16,351 | Efficiency of a transmitting antenna is the ratio of power actually radiated (in all directions) to the power absorbed by the antenna terminals. The power supplied to the antenna terminals which is not radiated is converted into heat. This is usually through loss resistance in the antenna's conductors, but can also be ... | [
{
"answer": "Efficiency",
"question": "A measure of the power that is useable and the power absorbed by the terminals?"
},
{
"answer": "heat",
"question": "What happens to the power that is not absorbed by the antenna?"
},
{
"answer": "magnetic core losses",
"question": "What can cau... |
16,352 | For instance, if a transmitter delivers 100 W into an antenna having an efficiency of 80%, then the antenna will radiate 80 W as radio waves and produce 20 W of heat. In order to radiate 100 W of power, one would need to use a transmitter capable of supplying 125 W to the antenna. Note that antenna efficiency is a sepa... | [
{
"answer": "100 W",
"question": "What would need to be placed into the transmitter to create ten W oh warmth? "
},
{
"answer": "electrical measurements",
"question": "What would need to be investigated to determine how much power was radiated?"
},
{
"answer": "impedance matching",
"... |
16,353 | However loss resistance will generally affect the feedpoint impedance, adding to its resistive (real) component. That resistance will consist of the sum of the radiation resistance Rr and the loss resistance Rloss. If an rms current I is delivered to the terminals of an antenna, then a power of I2Rr will be radiated an... | [
{
"answer": "loss resistance",
"question": "What can increase the feedpoint impedance of a component?"
},
{
"answer": "resistance",
"question": "The addition of Rr and Rloss equals what?"
},
{
"answer": "Rr / (Rr + Rloss)",
"question": "What equation an determine an antennas effectiv... |
16,354 | According to reciprocity, the efficiency of an antenna used as a receiving antenna is identical to the efficiency as defined above. The power that an antenna will deliver to a receiver (with a proper impedance match) is reduced by the same amount. In some receiving applications, the very inefficient antennas may have l... | [
{
"answer": "thermal noise floor",
"question": "What is the median level for measuring atmospheric noise?"
},
{
"answer": "receiving",
"question": "In what type of programs would low efficiency antennas not make a difference in effectiveness?"
},
{
"answer": "man-made noise",
"questi... |
16,355 | The definition of antenna gain or power gain already includes the effect of the antenna's efficiency. Therefore, if one is trying to radiate a signal toward a receiver using a transmitter of a given power, one need only compare the gain of various antennas rather than considering the efficiency as well. This is likewis... | [
{
"answer": "antenna gain",
"question": "What else is also known as power gain?"
},
{
"answer": "transmitter",
"question": "What is used to signal toward a reciever?"
},
{
"answer": "directive gain",
"question": "Which gain does not iclude the effect of an antenna?"
},
{
"ans... |
16,356 | This is fortunate, since antennas at lower frequencies which are not rather large (a good fraction of a wavelength in size) are inevitably inefficient (due to the small radiation resistance Rr of small antennas). Most AM broadcast radios (except for car radios) take advantage of this principle by including a small loop... | [
{
"answer": "inefficient",
"question": "Small and minimal frequency antennas are know to be what?"
},
{
"answer": "small loop antenna",
"question": "What is added to to increase ability for reception?"
},
{
"answer": "little effect",
"question": "How would this antenna rate in the gr... |
16,357 | The polarization of an antenna refers to the orientation of the electric field (E-plane) of the radio wave with respect to the Earth's surface and is determined by the physical structure of the antenna and by its orientation; note that this designation is totally distinct from the antenna's directionality. Thus, a simp... | [
{
"answer": "one",
"question": "How many polarizations will a antenna have when mounted vertically?"
},
{
"answer": "E-plane",
"question": "What is another name for electric-field?"
},
{
"answer": "transverse wave",
"question": "When is a magnetic fields right angles to a electrical ... |
16,358 | Reflections generally affect polarization. For radio waves, one important reflector is the ionosphere which can change the wave's polarization. Thus for signals received following reflection by the ionosphere (a skywave), a consistent polarization cannot be expected. For line-of-sight communications or ground wave prop... | [
{
"answer": "Reflections",
"question": "What mostly affects polarization?"
},
{
"answer": "ionosphere",
"question": "What reflector can change the waves polarization?"
},
{
"answer": "transmitter",
"question": "What will you be matching with the receiving antenna's polarization?"
... |
16,359 | Polarization is predictable from an antenna's geometry, although in some cases it is not at all obvious (such as for the quad antenna). An antenna's linear polarization is generally along the direction (as viewed from the receiving location) of the antenna's currents when such a direction can be defined. For instance, ... | [
{
"answer": "Polarization",
"question": "Whats predictable about an antenna's geometry?"
},
{
"answer": "commercial antenna",
"question": "The polarization of what antenna is essential specification?"
},
{
"answer": "horizontal",
"question": "Most rooftop antenna's are polarized in w... |
16,360 | Polarization is the sum of the E-plane orientations over time projected onto an imaginary plane perpendicular to the direction of motion of the radio wave. In the most general case, polarization is elliptical, meaning that the polarization of the radio waves varies over time. Two special cases are linear polarization (... | [
{
"answer": "imaginary plane",
"question": "What are electrical fields projected on to?"
},
{
"answer": "radio wave",
"question": "What is the imagenary plane perpindicular to?"
},
{
"answer": "elliptical",
"question": "What is the name to describe polarization of radio waves varies ... |
16,361 | It is best for the receiving antenna to match the polarization of the transmitted wave for optimum reception. Intermediate matchings will lose some signal strength, but not as much as a complete mismatch. A circularly polarized antenna can be used to equally well match vertical or horizontal linear polarizations. Trans... | [
{
"answer": "match the polarization",
"question": "What is the best for an recieving antenna for optimum reception?"
},
{
"answer": "Intermediate matchings",
"question": "What loses signal strength?"
},
{
"answer": "circularly polarized",
"question": "What is used to match vertical a... |
16,362 | Maximum power transfer requires matching the impedance of an antenna system (as seen looking into the transmission line) to the complex conjugate of the impedance of the receiver or transmitter. In the case of a transmitter, however, the desired matching impedance might not correspond to the dynamic output impedance of... | [
{
"answer": "Maximum power transfer",
"question": "What requires matching of the empedance to an antenna system?"
},
{
"answer": "\"tweak\" the match",
"question": "Why would a transmitter have additional adjustments?"
},
{
"answer": "standing wave ratio",
"question": "What is SWR?"
... |
16,363 | In some cases this is done in a more extreme manner, not simply to cancel a small amount of residual reactance, but to resonate an antenna whose resonance frequency is quite different from the intended frequency of operation. For instance, a "whip antenna" can be made significantly shorter than 1/4 wavelength long, for... | [
{
"answer": "whip antenna",
"question": "What can be shorter than 1/4 wavelength long?"
},
{
"answer": "capacitative reactance",
"question": "What is the opposite of inductive reactance?"
},
{
"answer": "loading coil",
"question": "What is at the base of the antenna?"
},
{
"a... |
16,364 | So an additional problem beyond canceling the unwanted reactance is of matching the remaining resistive impedance to the characteristic impedance of the transmission line. In principle this can always be done with a transformer, however the turns ratio of a transformer is not adjustable. A general matching network with... | [
{
"answer": "turns ratio",
"question": "What is not adjustable when it comes to a transformer?"
},
{
"answer": "50 or 75",
"question": "How many ohms are in are in a standard coax?"
},
{
"answer": "two adjustments",
"question": "A general matching network needs a minimum of how many ... |
16,365 | Unlike the above antennas, traveling wave antennas are nonresonant so they have inherently broad bandwidth. They are typically wire antennas multiple wavelengths long, through which the voltage and current waves travel in one direction, instead of bouncing back and forth to form standing waves as in resonant antennas. ... | [
{
"answer": "traveling wave antennas",
"question": "What antenna's are nonresonant?"
},
{
"answer": "one direction",
"question": "How long are the wire antenna's that the voltage and current waves travel in the same direction?"
},
{
"answer": "resistor",
"question": "What are undirec... |
16,366 | The radiation pattern and even the driving point impedance of an antenna can be influenced by the dielectric constant and especially conductivity of nearby objects. For a terrestrial antenna, the ground is usually one such object of importance. The antenna's height above the ground, as well as the electrical properties... | [
{
"answer": "dielectric constant",
"question": "What is the radiation patter influenced by?"
},
{
"answer": "terrestrial antenna",
"question": "The ground is important for what antenna?"
},
{
"answer": "artificial ground plane",
"question": "Whats another name for the ground?"
},
... |
16,367 | The net quality of a ground reflection depends on the topography of the surface. When the irregularities of the surface are much smaller than the wavelength, we are in the regime of specular reflection, and the receiver sees both the real antenna and an image of the antenna under the ground due to reflection. But if th... | [
{
"answer": "topography",
"question": "What is the net quality of the ground dependent of?"
},
{
"answer": "reflection",
"question": "What is the reason for the receiver seeing both the ral antenna and image of the antenna?"
},
{
"answer": "higher frequencies",
"question": "What freq... |
16,368 | The phase of reflection of electromagnetic waves depends on the polarization of the incident wave. Given the larger refractive index of the ground (typically n=2) compared to air (n=1), the phase of horizontally polarized radiation is reversed upon reflection (a phase shift of radians or 180°). On the other hand, the ... | [
{
"answer": "n=2",
"question": "What is the refractive index of the ground?"
},
{
"answer": "reflection",
"question": "When is polarized radiation reversed?"
},
{
"answer": "n=1",
"question": "What is the refractive index of air?"
},
{
"answer": "electrical conductor",
"q... |
16,369 | When an electromagnetic wave strikes a plane surface such as the ground, part of the wave is transmitted into the ground and part of it is reflected, according to the Fresnel coefficients. If the ground is a very good conductor then almost all of the wave is reflected (180° out of phase), whereas a ground modeled as a ... | [
{
"answer": "Fresnel coefficients",
"question": "Who proposed this theory?"
},
{
"answer": "180° out of phase",
"question": "Is the ground has a great conductor, how much of the wave will be reflected?"
},
{
"answer": "electromagnetic wave",
"question": "what is reflected and transmi... |
16,370 | The effective area or effective aperture of a receiving antenna expresses the portion of the power of a passing electromagnetic wave which it delivers to its terminals, expressed in terms of an equivalent area. For instance, if a radio wave passing a given location has a flux of 1 pW / m2 (10−12 watts per square meter)... | [
{
"answer": "aperture",
"question": "What is the portion of something that is reached by the radio transmission called?"
},
{
"answer": "direction",
"question": "What effects the function of signals received by an antenna?"
},
{
"answer": "microvolts",
"question": "What is a measure ... |
16,372 | For example, at 30 MHz (10 m wavelength) a true resonant 1⁄4-wavelength monopole would be almost 2.5 meters long, and using an antenna only 1.5 meters tall would require the addition of a loading coil. Then it may be said that the coil has lengthened the antenna to achieve an electrical length of 2.5 meters. However, t... | [
{
"answer": "loading coil",
"question": "What can be added to allow for an antenna shorter than the needed height to produce desired results?"
},
{
"answer": "lower",
"question": "How would the resistive impedance from this scenario compare to if the antenna was the proper height?"
},
{
... |
16,373 | Consider a half-wave dipole designed to work with signals 1 m wavelength, meaning the antenna would be approximately 50 cm across. If the element has a length-to-diameter ratio of 1000, it will have an inherent resistance of about 63 ohms. Using the appropriate transmission wire or balun, we match that resistance to en... | [
{
"answer": "50 cm",
"question": "How big would an antenna be used to with with one m wavelengths?"
},
{
"answer": "changing the matching system",
"question": "How could the rection of output be adressed by?"
},
{
"answer": "ampere",
"question": " What unit is used to measure current... |
16,374 | Recall that a current will reflect when there are changes in the electrical properties of the material. In order to efficiently send the signal into the transmission line, it is important that the transmission line has the same impedance as the elements, otherwise some of the signal will be reflected back into the ante... | [
{
"answer": "electrical",
"question": "What sort of changes in material would a current reflect?"
},
{
"answer": "impedance",
"question": " What must match between the transmission line and elements?"
},
{
"answer": "Impedance matching",
"question": "What technique is used to prevent... |
16,375 | An electromagnetic wave refractor in some aperture antennas is a component which due to its shape and position functions to selectively delay or advance portions of the electromagnetic wavefront passing through it. The refractor alters the spatial characteristics of the wave on one side relative to the other side. It c... | [
{
"answer": "selectively delay",
"question": "What is used to allow one to control the function of wave fronts moving through an antenna?"
},
{
"answer": "refractor",
"question": "What changes the structuak traits of a wave on either side?"
},
{
"answer": "spatial characteristics",
"... |
16,376 | The actual antenna which is transmitting the original wave then also may receive a strong signal from its own image from the ground. This will induce an additional current in the antenna element, changing the current at the feedpoint for a given feedpoint voltage. Thus the antenna's impedance, given by the ratio of fee... | [
{
"answer": "actual antenna",
"question": "What can receive a stron signal by transmitting an original wave?"
},
{
"answer": "antenna element",
"question": "Where will the additional current be induced?"
},
{
"answer": "antenna's impedance",
"question": "What is altered because of th... |
16,377 | For horizontal propagation between transmitting and receiving antennas situated near the ground reasonably far from each other, the distances traveled by tne direct and reflected rays are nearly the same. There is almost no relative phase shift. If the emission is polarized vertically, the two fields (direct and reflec... | [
{
"answer": "horizontal propagation",
"question": "What is between recieving and transmitting antenna's?"
},
{
"answer": "polarized vertically",
"question": "When is the emission at maximized recieved signal?"
},
{
"answer": "image at right",
"question": "Where is the radiation patte... |
16,378 | On the other hand, classical (analog) television transmissions are usually horizontally polarized, because in urban areas buildings can reflect the electromagnetic waves and create ghost images due to multipath propagation. Using horizontal polarization, ghosting is reduced because the amount of reflection of electroma... | [
{
"answer": "analog",
"question": "What is another name for classical television transmissions?"
},
{
"answer": "multipath propagation",
"question": "Buildings can create ghost images because of what?"
},
{
"answer": "horizontal polarization",
"question": "When is ghosting reduced?"
... |
16,379 | Current circulating in one antenna generally induces a voltage across the feedpoint of nearby antennas or antenna elements. The mathematics presented below are useful in analyzing the electrical behaviour of antenna arrays, where the properties of the individual array elements (such as half wave dipoles) are already kn... | [
{
"answer": "antenna arrays",
"question": "Where are the indiviual array elements known?"
},
{
"answer": "Current circulating",
"question": "What induces a feedpoint to antennas nearby?"
},
{
"answer": "electrical behaviour",
"question": "What are the mathmatic useful towards?"
},
... |
16,380 | This is a consequence of Lorentz reciprocity. For an antenna element not connected to anything (open circuited) one can write . But for an element which is short circuited, a current is generated across that short but no voltage is allowed, so the corresponding . This is the case, for instance, with the so-called par... | [
{
"answer": "open circuited",
"question": "a antenna element not connected to anything is circuited how?"
},
{
"answer": "short circuited",
"question": "When is the element not allowed voltage?"
},
{
"answer": "Parasitic",
"question": "What element absorbs and reradiate RF-energy?"
... |
16,381 | The difference in the above factors for the case of θ=0 is the reason that most broadcasting (transmissions intended for the public) uses vertical polarization. For receivers near the ground, horizontally polarized transmissions suffer cancellation. For best reception the receiving antennas for these signals are likewi... | [
{
"answer": "broadcasting",
"question": "What type of programmin relies on vertical polarization?"
},
{
"answer": "cancellation",
"question": "If you were to position your receiver closer to the ground what might be a negative of this placement?"
},
{
"answer": "mobile phones",
"ques... |
16,382 | Loop antennas consist of a loop or coil of wire. Loops with circumference of a wavelength or larger act similarly to dipole antennas. However loops small in comparison to a wavelength act differently. They interact with the magnetic field of the radio wave instead of the electric field as other antennas do, and so are ... | [
{
"answer": "Loop antennas",
"question": "What type of antenna can be formed by a circular segment of wire?"
},
{
"answer": "circumference of a wavelength",
"question": "What is a loop antenna compared with to determine its beahvior?"
},
{
"answer": "loops small",
"question": "If you... |
16,383 | It is a fundamental property of antennas that the electrical characteristics of an antenna described in the next section, such as gain, radiation pattern, impedance, bandwidth, resonant frequency and polarization, are the same whether the antenna is transmitting or receiving. For example, the "receiving pattern" (sensi... | [
{
"answer": "the same",
"question": "Are essential properties of an antenna changed based on what fungtion they are performing"
},
{
"answer": "reciprocity theorem of electromagnetics",
"question": "What proposition explains the equivalency of the recieving pattern of an antenna?"
},
{
"... |
16,384 | The flowering plants (angiosperms), also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants, with about 350,000 species. Like gymnosperms, angiosperms are seed-producing plants; they are distinguished from gymnosperms by characteristics including flowers, endosperm within the seeds, and t... | [
{
"answer": "angiosperms",
"question": "What are the most diverse group of land plants?"
},
{
"answer": "350,000",
"question": "How many species of flowering plants are there about?"
},
{
"answer": "an enclosure",
"question": "What does an angiosperm produce its seeds within?"
},
... |
16,387 | The evolution of seed plants and later angiosperms appears to be the result of two distinct rounds of whole genome duplication events. These occurred at 319 million years ago and 192 million years ago. Another possible whole genome duplication event at 160 million years ago perhaps created the ancestral line that led t... | [
{
"answer": "two",
"question": "How many distinct rounds of genome duplication events are suspected in the evolution of seed plants?"
},
{
"answer": "319 million years ago",
"question": "When did the first whole genome duplication event occur?"
},
{
"answer": "whole genome duplication",
... |
16,388 | The earliest known macrofossil confidently identified as an angiosperm, Archaefructus liaoningensis, is dated to about 125 million years BP (the Cretaceous period), whereas pollen considered to be of angiosperm origin takes the fossil record back to about 130 million years BP. However, one study has suggested that the ... | [
{
"answer": "about 125 million years BP",
"question": "When is the earliest known macrofossil identified as an angiosperm dated?"
},
{
"answer": "Archaefructus liaoningensis",
"question": "What is the earliest known angiosperm?"
},
{
"answer": "pollen",
"question": "What pushes the a... |
16,389 | The great angiosperm radiation, when a great diversity of angiosperms appears in the fossil record, occurred in the mid-Cretaceous (approximately 100 million years ago). However, a study in 2007 estimated that the division of the five most recent (the genus Ceratophyllum, the family Chloranthaceae, the eudicots, the ma... | [
{
"answer": "approximately 100 million years ago",
"question": "When does a great diversity of angiosperms appear in the fossil record?"
},
{
"answer": "great angiosperm radiation,",
"question": "What is the appearance of a large amount of angiosperms in the fossil record known as?"
},
{
... |
16,390 | Island genetics provides one proposed explanation for the sudden, fully developed appearance of flowering plants. Island genetics is believed to be a common source of speciation in general, especially when it comes to radical adaptations that seem to have required inferior transitional forms. Flowering plants may have ... | [
{
"answer": "Island genetics",
"question": "What is one proposed explanation for the instant appearance of flowering plants?"
},
{
"answer": "speciation",
"question": "What is island genetics thought to be a default source of?"
},
{
"answer": "inferior transitional forms",
"question"... |
16,391 | Animals are also involved in the distribution of seeds. Fruit, which is formed by the enlargement of flower parts, is frequently a seed-dispersal tool that attracts animals to eat or otherwise disturb it, incidentally scattering the seeds it contains (see frugivory). Although many such mutualistic relationships remain ... | [
{
"answer": "distribution of seeds",
"question": "What are animals also a part of?"
},
{
"answer": "Fruit",
"question": "What did the enlargement of flower parts evolve to form?"
},
{
"answer": "seed-dispersal",
"question": "What does a plant get out of forming fruit?"
},
{
"... |
16,392 | Flower ontogeny uses a combination of genes normally responsible for forming new shoots. The most primitive flowers probably had a variable number of flower parts, often separate from (but in contact with) each other. The flowers tended to grow in a spiral pattern, to be bisexual (in plants, this means both male and fe... | [
{
"answer": "Flower ontogeny",
"question": "What uses a combination of genes to form new shoots?"
},
{
"answer": "separate from (but in contact with) each other",
"question": "What were plant parts like in their primitive days?"
},
{
"answer": "grow in a spiral pattern",
"question": ... |
16,393 | Flower evolution continues to the present day; modern flowers have been so profoundly influenced by humans that some of them cannot be pollinated in nature. Many modern domesticated flower species were formerly simple weeds, which sprouted only when the ground was disturbed. Some of them tended to grow with human crops... | [
{
"answer": "present day",
"question": "How long has flower evolution occurred? "
},
{
"answer": "formerly simple weeds",
"question": "What heritage do many modern domesticated flower species have?"
},
{
"answer": "pollinated",
"question": "Humans have effected some flowers so much t... |
16,394 | The exact relationship between these eight groups is not yet clear, although there is agreement that the first three groups to diverge from the ancestral angiosperm were Amborellales, Nymphaeales, and Austrobaileyales. The term basal angiosperms refers to these three groups. Among the rest, the relationship between the... | [
{
"answer": "Amborellales, Nymphaeales, and Austrobaileyales",
"question": "What three groups were the first to diverge from angiosperm?"
},
{
"answer": "basal",
"question": "What term refers to the first three groups to diverge from angiosperm?"
},
{
"answer": "unclear",
"question":... |
16,397 | The internal classification of this group has undergone considerable revision. The Cronquist system, proposed by Arthur Cronquist in 1968 and published in its full form in 1981, is still widely used but is no longer believed to accurately reflect phylogeny. A consensus about how the flowering plants should be arranged ... | [
{
"answer": "how the flowering plants should be arranged",
"question": "What consensus is the AGP trying to reach?"
},
{
"answer": "classification",
"question": "What internal component has undergone considerable revision?"
},
{
"answer": "The Cronquist system",
"question": "What sys... |
16,398 | Recent studies, as by the APG, show that the monocots form a monophyletic group (clade) but that the dicots do not (they are paraphyletic). Nevertheless, the majority of dicot species do form a monophyletic group, called the eudicots or tricolpates. Of the remaining dicot species, most belong to a third major clade kno... | [
{
"answer": "monophyletic",
"question": "What type of groups do monocots form, based on a recent APG studies?"
},
{
"answer": "dicot",
"question": "Eudicots or tricolpates are part of a monophyletic group formed by what species?"
},
{
"answer": "magnoliids",
"question": "What third m... |
16,399 | The number of species of flowering plants is estimated to be in the range of 250,000 to 400,000. This compares to around 12,000 species of moss or 11,000 species of pteridophytes, showing that the flowering plants are much more diverse. The number of families in APG (1998) was 462. In APG II (2003) it is not settled; a... | [
{
"answer": "250,000 to 400,000",
"question": "What is the estimated range for the number of flowering plants?"
},
{
"answer": "12,000",
"question": "How many species of moss is there?"
},
{
"answer": "diverse",
"question": "What does the large number of flowering plant species indic... |
16,400 | In the dicotyledons, the bundles in the very young stem are arranged in an open ring, separating a central pith from an outer cortex. In each bundle, separating the xylem and phloem, is a layer of meristem or active formative tissue known as cambium. By the formation of a layer of cambium between the bundles (interfasc... | [
{
"answer": "an open ring",
"question": "What shape are the bundles in the young stem of dicotyledons arranged in?"
},
{
"answer": "xylem and phloem",
"question": "What does the cambium separate?"
},
{
"answer": "cambium",
"question": "What is a layer of meristem or formative tissue ... |
16,401 | The characteristic feature of angiosperms is the flower. Flowers show remarkable variation in form and elaboration, and provide the most trustworthy external characteristics for establishing relationships among angiosperm species. The function of the flower is to ensure fertilization of the ovule and development of fru... | [
{
"answer": "flower",
"question": "What is the defining feature of angiosperms?"
},
{
"answer": "form and elaboration",
"question": "What characteristic flowers show variation in?"
},
{
"answer": "establishing relationships among angiosperm species",
"question": "What do flowers prov... |
16,402 | The flower may consist only of these parts, as in willow, where each flower comprises only a few stamens or two carpels. Usually, other structures are present and serve to protect the sporophylls and to form an envelope attractive to pollinators. The individual members of these surrounding structures are known as sepal... | [
{
"answer": "only a few stamens or two carpels",
"question": "What is a willow's flower comprised of?"
},
{
"answer": "the sporophylls",
"question": "What have some structures evolved to protect?"
},
{
"answer": "green and leaf-like",
"question": "What appearance are calyx of sepals ... |
16,403 | While the majority of flowers are perfect or hermaphrodite (having both pollen and ovule producing parts in the same flower structure), flowering plants have developed numerous morphological and physiological mechanisms to reduce or prevent self-fertilization. Heteromorphic flowers have short carpels and long stamens, ... | [
{
"answer": "hermaphrodite",
"question": "What sexual feature do a majority of flowers demonstrate?"
},
{
"answer": "reduce or prevent self-fertilization",
"question": "Why did flowering plants develop numerous morphological and physiological mechanisms?"
},
{
"answer": "so animal pollin... |
16,405 | The character of the seed coat bears a definite relation to that of the fruit. They protect the embryo and aid in dissemination; they may also directly promote germination. Among plants with indehiscent fruits, in general, the fruit provides protection for the embryo and secures dissemination. In this case, the seed co... | [
{
"answer": "the fruit",
"question": "The appearance of the seed coat bears a definite relation to that of what?"
},
{
"answer": "embryo",
"question": "What does the seed coat protect?"
},
{
"answer": "dissemination",
"question": "What does the fruit of the flower secure?"
},
{
... |
16,406 | Agriculture is almost entirely dependent on angiosperms, which provide virtually all plant-based food, and also provide a significant amount of livestock feed. Of all the families of plants, the Poaceae, or grass family (grains), is by far the most important, providing the bulk of all feedstocks (rice, corn — maize, wh... | [
{
"answer": "angiosperms",
"question": "On what is agriculture almost completely dependent?"
},
{
"answer": "Poaceae",
"question": "What family of plants is most important for human sustenance?"
},
{
"answer": "legume",
"question": "What is the more common name of the Fabaceae?"
},... |
16,407 | Hyderabad (i/ˈhaɪdərəˌbæd/ HY-dər-ə-bad; often /ˈhaɪdrəˌbæd/) is the capital of the southern Indian state of Telangana and de jure capital of Andhra Pradesh.[A] Occupying 650 square kilometres (250 sq mi) along the banks of the Musi River, it has a population of about 6.7 million and a metropolitan population of about ... | [
{
"answer": "Hyderabad (i/ˈhaɪdərəˌbæd/ HY-dər-ə-bad; often /ˈhaɪdrəˌbæd/) is the capital of the southern Indian state of Telangana",
"question": "Which city is the capital of Telangana?"
},
{
"answer": "250 sq mi",
"question": "How many square miles does Hyderabad cover?"
},
{
"answer":... |
16,408 | Established in 1591 by Muhammad Quli Qutb Shah, Hyderabad remained under the rule of the Qutb Shahi dynasty for nearly a century before the Mughals captured the region. In 1724, Mughal viceroy Asif Jah I declared his sovereignty and created his own dynasty, known as the Nizams of Hyderabad. The Nizam's dominions became... | [
{
"answer": "Established in 1591",
"question": "In what year was Hyderabad established?"
},
{
"answer": "Muhammad Quli Qutb Shah",
"question": "Who is the person that established Hyderabad?"
},
{
"answer": "the Qutb Shahi dynasty",
"question": "What dynasty controlled Hyderabad until... |
16,409 | Relics of Qutb Shahi and Nizam rule remain visible today, with the Charminar—commissioned by Muhammad Quli Qutb Shah—coming to symbolise Hyderabad. Golconda fort is another major landmark. The influence of Mughlai culture is also evident in the city's distinctive cuisine, which includes Hyderabadi biryani and Hyderabad... | [
{
"answer": "Muhammad Quli Qutb",
"question": "Which individual commissioned Chaminar?"
},
{
"answer": "the mid-19th century",
"question": "When did Hyderabad become important culturally in India?"
},
{
"answer": "The Qutb Shahis and Nizams",
"question": "Which two groups had an infl... |
16,410 | Hyderabad was historically known as a pearl and diamond trading centre, and it continues to be known as the City of Pearls. Many of the city's traditional bazaars, including Laad Bazaar, Begum Bazaar and Sultan Bazaar, have remained open for centuries. However, industrialisation throughout the 20th century attracted ma... | [
{
"answer": "pearl and diamond",
"question": "What items had been historically traded in Hyderabad?"
},
{
"answer": "City of Pearls",
"question": "What is a nickname for Hyderabad?"
},
{
"answer": "Laad Bazaar, Begum Bazaar and Sultan Bazaar",
"question": "What are three historic baz... |
16,411 | According to John Everett-Heath, the author of Oxford Concise Dictionary of World Place Names, Hyderabad means "Haydar's city" or "lion city", from haydar (lion) and ābād (city). It was named to honour the Caliph Ali Ibn Abi Talib, who was also known as Haydar because of his lion-like valour in battles. Andrew Petersen... | [
{
"answer": "\"Haydar's city\" or \"lion city\"",
"question": "What does the Oxford Concise Dictionary of World Place Names say Hyderabad means?"
},
{
"answer": "Caliph Ali Ibn Abi Talib",
"question": "Hyderabad was named in honor of someone, who was it?"
},
{
"answer": "Baghnagar (city ... |
16,412 | Archaeologists excavating near the city have unearthed Iron Age sites that may date from 500 BCE. The region comprising modern Hyderabad and its surroundings was known as Golkonda (Golla Konda-"shepherd's hill"), and was ruled by the Chalukya dynasty from 624 CE to 1075 CE. Following the dissolution of the Chalukya emp... | [
{
"answer": "500 BCE",
"question": "There may be Iron Age findings near Hyderabad, what age are they thought to be from?"
},
{
"answer": "624 CE to 1075 CE",
"question": "What time period did the Chalukya dynasty rule the Hyderabad region?"
},
{
"answer": "the 11th century",
"questio... |
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