answer string | choices dict | id string | kind string | lang string | question string | steps list | subject string | text string | topic string |
|---|---|---|---|---|---|---|---|---|---|
Rychlost je 300 m/s. | {
"A": "250 m/s",
"B": "300 m/s",
"C": "350 m/s",
"D": "400 m/s"
} | phy_0401 | multiple_choice | cs | Vlna na struně má f = 150 Hz a λ = 2 m. Jaká je její rychlost? | [
"v = 150 Hz × 2 m.",
"v = 300 m/s.",
"Vyber možnost B."
] | physics | Answer: 300 m/s
Steps:
1. v = 150 Hz × 2 m.
2. v = 300 m/s.
3. Vyber možnost B.
Answer: (B) | waves |
It dramatizes superposition at large scale, questioning measurement. | null | phy_0402 | concept | en | Why Schrödinger's cat? | [
"It dramatizes superposition at large scale, questioning measurement.",
"So the answer stands: It dramatizes superposition at large scale, questioning measurement."
] | physics | Answer: It dramatizes superposition at large scale, questioning measurement.
Steps:
1. It dramatizes superposition at large scale, questioning measurement.
2. So the answer stands: It dramatizes superposition at large scale, questioning measurement. | modern |
Work: 160 J. | null | phy_0403 | worked_example | en | A force of 40 N pushes 4 m. Compute the work done. | [
"W = F×d.",
"W = 40 N × 4 m.",
"= 160 J."
] | physics | Answer: Work: 160 J.
Steps:
1. W = F×d.
2. W = 40 N × 4 m.
3. = 160 J. | mechanics |
U rovná se RI pro rezistory. | null | phy_0404 | concept | cs | Proč Ohmův zákon? | [
"U rovná se RI pro rezistory.",
"Odpověď tedy platí: U rovná se RI pro rezistory."
] | physics | Answer: U rovná se RI pro rezistory.
Steps:
1. U rovná se RI pro rezistory.
2. Odpověď tedy platí: U rovná se RI pro rezistory. | electromagnetism |
Heat: 66976 J. | null | phy_0405 | worked_example | en | How much heat warms 2 kg of water by 8 K? (c = 4186 J/(kg·K)) | [
"Q = 2 kg × 4186 J/(kg·K) × 8 K.",
"= 66976 J."
] | physics | Answer: Heat: 66976 J.
Steps:
1. Q = 2 kg × 4186 J/(kg·K) × 8 K.
2. = 66976 J. | thermodynamics |
Apparent depth: 80 cm. | null | phy_0406 | worked_example | en | An object sits 120 cm deep in glass (n = 1.5). Compute the apparent depth. | [
"d' = d/n.",
"d' = 120 cm / 1.5.",
"= 80 cm."
] | physics | Answer: Apparent depth: 80 cm.
Steps:
1. d' = d/n.
2. d' = 120 cm / 1.5.
3. = 80 cm. | optics |
Motion shifts heard frequency up approaching, down receding. | null | phy_0407 | concept | en | What is the Doppler effect? | [
"Motion shifts heard frequency up approaching, down receding.",
"So the answer stands: Motion shifts heard frequency up approaching, down receding."
] | physics | Answer: Motion shifts heard frequency up approaching, down receding.
Steps:
1. Motion shifts heard frequency up approaching, down receding.
2. So the answer stands: Motion shifts heard frequency up approaching, down receding. | waves |
Lines: 55. | null | phy_0408 | worked_example | en | An atom is excited to level n = 11. Count the spectral lines it can emit. | [
"Pairs: 11×10/2.",
"= 110/2.",
"= 55."
] | physics | Answer: Lines: 55.
Steps:
1. Pairs: 11×10/2.
2. = 110/2.
3. = 55. | modern |
Speed is 13 m/s. | {
"A": "13 m/s",
"B": "12 m/s",
"C": "14 m/s",
"D": "15 m/s"
} | phy_0409 | multiple_choice | en | A car travels 130 m in 10 s. What is its speed? | [
"v = 130 m / 10 s.",
"v = 13 m/s.",
"Select option A."
] | physics | Answer: 13 m/s
Steps:
1. v = 130 m / 10 s.
2. v = 13 m/s.
3. Select option A.
Answer: (A) | mechanics |
Voltage: 96 V. | null | phy_0410 | worked_example | en | A current of 8 A flows through 12 Ω. Compute the voltage. | [
"V = I×R.",
"V = 8 A × 12 Ω.",
"= 96 V."
] | physics | Answer: Voltage: 96 V.
Steps:
1. V = I×R.
2. V = 8 A × 12 Ω.
3. = 96 V. | electromagnetism |
Odpověď je entropie. | {
"A": "entropie",
"B": "energie",
"C": "hmotnost",
"D": "náboj"
} | phy_0411 | multiple_choice | cs | Vyber: co nikdy neklesá izolovaně? | [
"Druhý zákon vládne.",
"Tedy: entropie.",
"Vyber možnost A."
] | physics | Answer: entropie
Steps:
1. Druhý zákon vládne.
2. Tedy: entropie.
3. Vyber možnost A.
Answer: (A) | thermodynamics |
Magnification: 9×. | null | phy_0412 | worked_example | en | An image forms 90 cm from a lens, object at 10 cm. Compute the magnification. | [
"M = di/do.",
"M = 90 cm / 10 cm.",
"= 9×."
] | physics | Answer: Magnification: 9×.
Steps:
1. M = di/do.
2. M = 90 cm / 10 cm.
3. = 9×. | optics |
Maximální výchylka, určuje hlasitost. | null | phy_0413 | concept | cs | Co je amplituda? | [
"Maximální výchylka, určuje hlasitost.",
"Odpověď tedy platí: Maximální výchylka, určuje hlasitost."
] | physics | Answer: Maximální výchylka, určuje hlasitost.
Steps:
1. Maximální výchylka, určuje hlasitost.
2. Odpověď tedy platí: Maximální výchylka, určuje hlasitost. | waves |
Odpověď je časoprostor. | {
"A": "kosmická loď",
"B": "jízdní řád",
"C": "pracovní stůl",
"D": "časoprostor"
} | phy_0414 | multiple_choice | cs | Vyber: co se zakřivuje společně? | [
"c pevné pro všechny.",
"Tedy: časoprostor.",
"Vyber možnost D."
] | physics | Answer: časoprostor
Steps:
1. c pevné pro všechny.
2. Tedy: časoprostor.
3. Vyber možnost D.
Answer: (D) | modern |
Kinetic energy is 49 J. | {
"A": "42 J",
"B": "49 J",
"C": "56 J",
"D": "63 J"
} | phy_0415 | multiple_choice | en | A 2 kg ball moves at 7 m/s. What is its kinetic energy? | [
"KE = ½×2 kg×(7 m/s)².",
"KE = 49 J.",
"Select option B."
] | physics | Answer: 49 J
Steps:
1. KE = ½×2 kg×(7 m/s)².
2. KE = 49 J.
3. Select option B.
Answer: (B) | mechanics |
Energy: 1200 J. | null | phy_0416 | worked_example | en | A 100 W heater runs for 12 s. Compute the energy used. | [
"E = P×t.",
"E = 100 W × 12 s.",
"= 1200 J."
] | physics | Answer: Energy: 1200 J.
Steps:
1. E = P×t.
2. E = 100 W × 12 s.
3. = 1200 J. | electromagnetism |
Halving volume doubles pressure at fixed temperature, squeezing gas harder. | null | phy_0417 | concept | en | Why Boyle's law? | [
"Halving volume doubles pressure at fixed temperature, squeezing gas harder.",
"So the answer stands: Halving volume doubles pressure at fixed temperature, squeezing gas harder."
] | physics | Answer: Halving volume doubles pressure at fixed temperature, squeezing gas harder.
Steps:
1. Halving volume doubles pressure at fixed temperature, squeezing gas harder.
2. So the answer stands: Halving volume doubles pressure at fixed temperature, squeezing gas harder. | thermodynamics |
The answer is Total internal. | {
"A": "Partial entry",
"B": "Gentle exit",
"C": "Total internal",
"D": "Soft landing"
} | phy_0418 | multiple_choice | en | Choose: what reflects all inside? | [
"Gems sparkle.",
"So: Total internal.",
"Select option C."
] | physics | Answer: Total internal
Steps:
1. Gems sparkle.
2. So: Total internal.
3. Select option C.
Answer: (C) | optics |
Supersonic objects pile waves into one loud shock cone. | null | phy_0419 | concept | en | Why sonic boom? | [
"Supersonic objects pile waves into one loud shock cone.",
"So the answer stands: Supersonic objects pile waves into one loud shock cone."
] | physics | Answer: Supersonic objects pile waves into one loud shock cone.
Steps:
1. Supersonic objects pile waves into one loud shock cone.
2. So the answer stands: Supersonic objects pile waves into one loud shock cone. | waves |
Count: 15. | {
"A": "15",
"B": "14",
"C": "16",
"D": "17"
} | phy_0420 | multiple_choice | en | An atom is excited to level n = 6. How many spectral lines can it emit? | [
"Pairs: 6×5/2.",
"Lines: 15.",
"Select option A."
] | physics | Answer: 15
Steps:
1. Pairs: 6×5/2.
2. Lines: 15.
3. Select option A.
Answer: (A) | modern |
Odpověď je nulová výsledná síla. | {
"A": "velké tření",
"B": "silný vítr",
"C": "hlasitý hluk",
"D": "nulová výsledná síla"
} | phy_0421 | multiple_choice | cs | Vyber: co drží rychlost? | [
"První zákon vládne.",
"Tedy: nulová výsledná síla.",
"Vyber možnost D."
] | physics | Answer: nulová výsledná síla
Steps:
1. První zákon vládne.
2. Tedy: nulová výsledná síla.
3. Vyber možnost D.
Answer: (D) | mechanics |
Alternating current reverses sinusoidally, suiting transformers and long lines. | null | phy_0422 | concept | en | What is AC? | [
"Alternating current reverses sinusoidally, suiting transformers and long lines.",
"So the answer stands: Alternating current reverses sinusoidally, suiting transformers and long lines."
] | physics | Answer: Alternating current reverses sinusoidally, suiting transformers and long lines.
Steps:
1. Alternating current reverses sinusoidally, suiting transformers and long lines.
2. So the answer stands: Alternating current reverses sinusoidally, suiting transformers and long lines. | electromagnetism |
The answer is Ideal gas. | {
"A": "Real solid",
"B": "Cold plasma",
"C": "Ideal gas",
"D": "Dark matter"
} | phy_0423 | multiple_choice | en | Choose: what obeys pV=nRT? | [
"Points collide elastic.",
"So: Ideal gas.",
"Select option C."
] | physics | Answer: Ideal gas
Steps:
1. Points collide elastic.
2. So: Ideal gas.
3. Select option C.
Answer: (C) | thermodynamics |
Odpověď je hranol. | {
"A": "hranol",
"B": "zrcadlo",
"C": "čočka",
"D": "stínítko"
} | phy_0424 | multiple_choice | cs | Vyber: co dělí bílé? | [
"Barvy rozvějířeny.",
"Tedy: hranol.",
"Vyber možnost A."
] | physics | Answer: hranol
Steps:
1. Barvy rozvějířeny.
2. Tedy: hranol.
3. Vyber možnost A.
Answer: (A) | optics |
Matched driving builds huge oscillation, tuning instruments and bridges. | null | phy_0425 | concept | en | What is resonance? | [
"Matched driving builds huge oscillation, tuning instruments and bridges.",
"So the answer stands: Matched driving builds huge oscillation, tuning instruments and bridges."
] | physics | Answer: Matched driving builds huge oscillation, tuning instruments and bridges.
Steps:
1. Matched driving builds huge oscillation, tuning instruments and bridges.
2. So the answer stands: Matched driving builds huge oscillation, tuning instruments and bridges. | waves |
Particles leak through forbidden barriers, powering suns and chips. | null | phy_0426 | concept | en | What is tunnelling? | [
"Particles leak through forbidden barriers, powering suns and chips.",
"So the answer stands: Particles leak through forbidden barriers, powering suns and chips."
] | physics | Answer: Particles leak through forbidden barriers, powering suns and chips.
Steps:
1. Particles leak through forbidden barriers, powering suns and chips.
2. So the answer stands: Particles leak through forbidden barriers, powering suns and chips. | modern |
Stored energy like mgh waits to convert, powering falls and springs. | null | phy_0427 | concept | en | What is potential energy? | [
"Stored energy like mgh waits to convert, powering falls and springs.",
"So the answer stands: Stored energy like mgh waits to convert, powering falls and springs."
] | physics | Answer: Stored energy like mgh waits to convert, powering falls and springs.
Steps:
1. Stored energy like mgh waits to convert, powering falls and springs.
2. So the answer stands: Stored energy like mgh waits to convert, powering falls and springs. | mechanics |
Power: 243 W. | null | phy_0428 | worked_example | en | A current of 9 A flows through 3 Ω. Compute the dissipated power. | [
"P = I²×R.",
"P = (9 A)² × 3 Ω.",
"= 243 W."
] | physics | Answer: Power: 243 W.
Steps:
1. P = I²×R.
2. P = (9 A)² × 3 Ω.
3. = 243 W. | electromagnetism |
Power: 120 W. | null | phy_0429 | worked_example | en | An engine does 1200 J of work in 10 s. Compute its power. | [
"P = W/t.",
"P = 1200 J / 10 s.",
"= 120 W."
] | physics | Answer: Power: 120 W.
Steps:
1. P = W/t.
2. P = 1200 J / 10 s.
3. = 120 W. | thermodynamics |
Time: 7.3 s. | null | phy_0430 | worked_example | en | Light travels 22×10⁸ m. Compute the travel time. (c = 3×10⁸ m/s) | [
"t = d/c.",
"t = 22×10⁸ / 3×10⁸ s.",
"= 7.3 s."
] | physics | Answer: Time: 7.3 s.
Steps:
1. t = d/c.
2. t = 22×10⁸ / 3×10⁸ s.
3. = 7.3 s. | optics |
Period is 0.2 s. | {
"A": "0.2 s",
"B": "0.17 s",
"C": "0.14 s",
"D": "0.25 s"
} | phy_0431 | multiple_choice | en | A wave has frequency 5 Hz. What is its period? | [
"T = 1 / 5 Hz.",
"T = 0.2 s.",
"Select option A."
] | physics | Answer: 0.2 s
Steps:
1. T = 1 / 5 Hz.
2. T = 0.2 s.
3. Select option A.
Answer: (A) | waves |
Hmotnost je zmrazená energie. | null | phy_0432 | concept | cs | Proč E rovná se mc²? | [
"Hmotnost je zmrazená energie.",
"Odpověď tedy platí: Hmotnost je zmrazená energie."
] | physics | Answer: Hmotnost je zmrazená energie.
Steps:
1. Hmotnost je zmrazená energie.
2. Odpověď tedy platí: Hmotnost je zmrazená energie. | modern |
The answer is Friction. | {
"A": "Gravity",
"B": "Inertia",
"C": "Friction",
"D": "Vacuum"
} | phy_0433 | multiple_choice | en | Choose: what opposes sliding? | [
"Surfaces grip.",
"So: Friction.",
"Select option C."
] | physics | Answer: Friction
Steps:
1. Surfaces grip.
2. So: Friction.
3. Select option C.
Answer: (C) | mechanics |
Energie: 600 J. | null | phy_0434 | worked_example | cs | Topidlo 100 W běží po 6 s. Spočítej spotřebovanou energii. | [
"E = P×t.",
"E = 100 W × 6 s.",
"= 600 J."
] | physics | Answer: Energie: 600 J.
Steps:
1. E = P×t.
2. E = 100 W × 6 s.
3. = 600 J. | electromagnetism |
Temperature: 296 K. | null | phy_0435 | worked_example | en | Temperature is 23 °C. Convert it to kelvin. | [
"Add 273.",
"23 + 273.",
"= 296 K."
] | physics | Answer: Temperature: 296 K.
Steps:
1. Add 273.
2. 23 + 273.
3. = 296 K. | thermodynamics |
The answer is Fibre optics. | {
"A": "Copper bells",
"B": "Smoke signals",
"C": "Carrier owls",
"D": "Fibre optics"
} | phy_0436 | multiple_choice | en | Choose: what pipes internet? | [
"Light guided far.",
"So: Fibre optics.",
"Select option D."
] | physics | Answer: Fibre optics
Steps:
1. Light guided far.
2. So: Fibre optics.
3. Select option D.
Answer: (D) | optics |
Distance: 3400 m. | null | phy_0437 | worked_example | en | Thunder is heard 10 s after lightning. How far away is the storm? (v = 340 m/s) | [
"d = v×t.",
"d = 340 m/s × 10 s.",
"= 3400 m."
] | physics | Answer: Distance: 3400 m.
Steps:
1. d = v×t.
2. d = 340 m/s × 10 s.
3. = 3400 m. | waves |
Mass number: 21. | null | phy_0438 | worked_example | en | A nucleus has 10 protons and 11 neutrons. Compute its mass number. | [
"A = Z+N.",
"A = 10 + 11.",
"= 21."
] | physics | Answer: Mass number: 21.
Steps:
1. A = Z+N.
2. A = 10 + 11.
3. = 21. | modern |
The answer is Torque. | {
"A": "Work",
"B": "Power",
"C": "Energy",
"D": "Torque"
} | phy_0439 | multiple_choice | en | Choose: what twists rotations? | [
"Lever arm matters.",
"So: Torque.",
"Select option D."
] | physics | Answer: Torque
Steps:
1. Lever arm matters.
2. So: Torque.
3. Select option D.
Answer: (D) | mechanics |
Root-mean-square matches AC heating to DC, quoting fair 230 V mains. | null | phy_0440 | concept | en | Why RMS values? | [
"Root-mean-square matches AC heating to DC, quoting fair 230 V mains.",
"So the answer stands: Root-mean-square matches AC heating to DC, quoting fair 230 V mains."
] | physics | Answer: Root-mean-square matches AC heating to DC, quoting fair 230 V mains.
Steps:
1. Root-mean-square matches AC heating to DC, quoting fair 230 V mains.
2. So the answer stands: Root-mean-square matches AC heating to DC, quoting fair 230 V mains. | electromagnetism |
Temperature is 296 K. | {
"A": "295 K",
"B": "297 K",
"C": "298 K",
"D": "296 K"
} | phy_0441 | multiple_choice | en | Room temperature is 23 °C. What is it in kelvin? | [
"23 °C + 273.",
"= 296 K.",
"Select option D."
] | physics | Answer: 296 K
Steps:
1. 23 °C + 273.
2. = 296 K.
3. Select option D.
Answer: (D) | thermodynamics |
Particles redirect light by size, blue skies from tiny air molecules. | null | phy_0442 | concept | en | What is scattering? | [
"Particles redirect light by size, blue skies from tiny air molecules.",
"So the answer stands: Particles redirect light by size, blue skies from tiny air molecules."
] | physics | Answer: Particles redirect light by size, blue skies from tiny air molecules.
Steps:
1. Particles redirect light by size, blue skies from tiny air molecules.
2. So the answer stands: Particles redirect light by size, blue skies from tiny air molecules. | optics |
Perioda je 0,33 s. | {
"A": "0,25 s",
"B": "0,2 s",
"C": "0,33 s",
"D": "0,5 s"
} | phy_0443 | multiple_choice | cs | Vlna má frekvenci 3 Hz. Jaká je její perioda? | [
"T = 1 / 3 Hz.",
"T = 0,33 s.",
"Vyber možnost C."
] | physics | Answer: 0,33 s
Steps:
1. T = 1 / 3 Hz.
2. T = 0,33 s.
3. Vyber možnost C.
Answer: (C) | waves |
Survivors: 1800. | null | phy_0444 | worked_example | en | A sample of 7200 atoms undergoes 2 half-lives. Compute the survivors. | [
"Halve: 7200 → 3600.",
"Halve: 3600 → 1800.",
"= 1800."
] | physics | Answer: Survivors: 1800.
Steps:
1. Halve: 7200 → 3600.
2. Halve: 3600 → 1800.
3. = 1800. | modern |
Momentum: 33 kg·m/s. | null | phy_0445 | worked_example | en | A mass of 11 kg moves at 3 m/s. Compute its momentum. | [
"p = m×v.",
"p = 11 kg × 3 m/s.",
"= 33 kg·m/s."
] | physics | Answer: Momentum: 33 kg·m/s.
Steps:
1. p = m×v.
2. p = 11 kg × 3 m/s.
3. = 33 kg·m/s. | mechanics |
Výkon: 27 W. | null | phy_0446 | worked_example | cs | Proud 3 A teče přes 3 Ω. Spočítej ztrátový výkon. | [
"P = I²×R.",
"P = (3 A)² × 3 Ω.",
"= 27 W."
] | physics | Answer: Výkon: 27 W.
Steps:
1. P = I²×R.
2. P = (3 A)² × 3 Ω.
3. = 27 W. | electromagnetism |
Heat needed is 20930 J. | {
"A": "20930 J",
"B": "16744 J",
"C": "25116 J",
"D": "29302 J"
} | phy_0447 | multiple_choice | en | How much heat warms 1 kg of water by 5 K? (c = 4186 J/(kg·K)) | [
"Q = 1 kg × 4186 J/(kg·K) × 5 K.",
"Q = 20930 J.",
"Select option A."
] | physics | Answer: 20930 J
Steps:
1. Q = 1 kg × 4186 J/(kg·K) × 5 K.
2. Q = 20930 J.
3. Select option A.
Answer: (A) | thermodynamics |
Apparent depth: 90 cm. | null | phy_0448 | worked_example | en | An object sits 135 cm deep in glass (n = 1.5). Compute the apparent depth. | [
"d' = d/n.",
"d' = 135 cm / 1.5.",
"= 90 cm."
] | physics | Answer: Apparent depth: 90 cm.
Steps:
1. d' = d/n.
2. d' = 135 cm / 1.5.
3. = 90 cm. | optics |
Je sekund na cyklus, převrácená frekvence. | null | phy_0449 | concept | cs | Proč perioda? | [
"Je sekund na cyklus, převrácená frekvence.",
"Odpověď tedy platí: Je sekund na cyklus, převrácená frekvence."
] | physics | Answer: Je sekund na cyklus, převrácená frekvence.
Steps:
1. Je sekund na cyklus, převrácená frekvence.
2. Odpověď tedy platí: Je sekund na cyklus, převrácená frekvence. | waves |
Mass number is 10. | {
"A": "9",
"B": "10",
"C": "11",
"D": "12"
} | phy_0450 | multiple_choice | en | A nucleus has 5 protons and 5 neutrons. What is its mass number? | [
"A = 5 + 5.",
"A = 10.",
"Select option B."
] | physics | Answer: 10
Steps:
1. A = 5 + 5.
2. A = 10.
3. Select option B.
Answer: (B) | modern |
Net force: 20 N. | null | phy_0451 | worked_example | en | A mass of 10 kg accelerates at 2 m/s². Compute the net force. | [
"F = m×a.",
"F = 10 kg × 2 m/s².",
"= 20 N."
] | physics | Answer: Net force: 20 N.
Steps:
1. F = m×a.
2. F = 10 kg × 2 m/s².
3. = 20 N. | mechanics |
The answer is Maxwell's equations. | {
"A": "Newton's laws",
"B": "Kepler's laws",
"C": "Maxwell's equations",
"D": "Ohm's laws"
} | phy_0452 | multiple_choice | en | Choose: what unifies four laws? | [
"Light predicted.",
"So: Maxwell's equations.",
"Select option C."
] | physics | Answer: Maxwell's equations
Steps:
1. Light predicted.
2. So: Maxwell's equations.
3. Select option C.
Answer: (C) | electromagnetism |
Volume grows with Kelvin temperature at fixed pressure, expanding balloons. | null | phy_0453 | concept | en | What is Charles's law? | [
"Volume grows with Kelvin temperature at fixed pressure, expanding balloons.",
"So the answer stands: Volume grows with Kelvin temperature at fixed pressure, expanding balloons."
] | physics | Answer: Volume grows with Kelvin temperature at fixed pressure, expanding balloons.
Steps:
1. Volume grows with Kelvin temperature at fixed pressure, expanding balloons.
2. So the answer stands: Volume grows with Kelvin temperature at fixed pressure, expanding balloons. | thermodynamics |
Zvětšení je 3×. | {
"A": "2×",
"B": "3×",
"C": "4×",
"D": "5×"
} | phy_0454 | multiple_choice | cs | Obraz vzniká 30 cm od čočky, předmět v 10 cm. Jaké je zvětšení? | [
"M = 30 cm / 10 cm.",
"M = 3×.",
"Vyber možnost B."
] | physics | Answer: 3×
Steps:
1. M = 30 cm / 10 cm.
2. M = 3×.
3. Vyber možnost B.
Answer: (B) | optics |
3rd harmonic is 420 Hz. | {
"A": "390 Hz",
"B": "420 Hz",
"C": "450 Hz",
"D": "480 Hz"
} | phy_0455 | multiple_choice | en | A string's fundamental is 140 Hz. What is its 3rd harmonic? | [
"f3 = 3 × 140 Hz.",
"f3 = 420 Hz.",
"Select option B."
] | physics | Answer: 420 Hz
Steps:
1. f3 = 3 × 140 Hz.
2. f3 = 420 Hz.
3. Select option B.
Answer: (B) | waves |
Lines: 66. | null | phy_0456 | worked_example | en | An atom is excited to level n = 12. Count the spectral lines it can emit. | [
"Pairs: 12×11/2.",
"= 132/2.",
"= 66."
] | physics | Answer: Lines: 66.
Steps:
1. Pairs: 12×11/2.
2. = 132/2.
3. = 66. | modern |
Work: 180 J. | null | phy_0457 | worked_example | en | A force of 45 N pushes 4 m. Compute the work done. | [
"W = F×d.",
"W = 45 N × 4 m.",
"= 180 J."
] | physics | Answer: Work: 180 J.
Steps:
1. W = F×d.
2. W = 45 N × 4 m.
3. = 180 J. | mechanics |
Napětí: 36 V. | null | phy_0458 | worked_example | cs | Proud 3 A teče přes 12 Ω. Spočítej napětí. | [
"U = I×R.",
"U = 3 A × 12 Ω.",
"= 36 V."
] | physics | Answer: Napětí: 36 V.
Steps:
1. U = I×R.
2. U = 3 A × 12 Ω.
3. = 36 V. | electromagnetism |
Srážející se částice předávají energii. | null | phy_0459 | concept | cs | Proč vedení tepla? | [
"Srážející se částice předávají energii.",
"Odpověď tedy platí: Srážející se částice předávají energii."
] | physics | Answer: Srážející se částice předávají energii.
Steps:
1. Srážející se částice předávají energii.
2. Odpověď tedy platí: Srážející se částice předávají energii. | thermodynamics |
Magnification: 10×. | null | phy_0460 | worked_example | en | An image forms 100 cm from a lens, object at 10 cm. Compute the magnification. | [
"M = di/do.",
"M = 100 cm / 10 cm.",
"= 10×."
] | physics | Answer: Magnification: 10×.
Steps:
1. M = di/do.
2. M = 100 cm / 10 cm.
3. = 10×. | optics |
3rd harmonic: 540 Hz. | null | phy_0461 | worked_example | en | A string's fundamental is 180 Hz. Compute its 3rd harmonic. | [
"f3 = 3×f1.",
"f3 = 3 × 180 Hz.",
"= 540 Hz."
] | physics | Answer: 3rd harmonic: 540 Hz.
Steps:
1. f3 = 3×f1.
2. f3 = 3 × 180 Hz.
3. = 540 Hz. | waves |
Mass number: 23. | null | phy_0462 | worked_example | en | A nucleus has 11 protons and 12 neutrons. Compute its mass number. | [
"A = Z+N.",
"A = 11 + 12.",
"= 23."
] | physics | Answer: Mass number: 23.
Steps:
1. A = Z+N.
2. A = 11 + 12.
3. = 23. | modern |
Net force is 18 N. | {
"A": "18 N",
"B": "15 N",
"C": "21 N",
"D": "24 N"
} | phy_0463 | multiple_choice | en | A mass of 6 kg accelerates at 3 m/s². What is the net force? | [
"F = 6 kg × 3 m/s².",
"F = 18 N.",
"Select option A."
] | physics | Answer: 18 N
Steps:
1. F = 6 kg × 3 m/s².
2. F = 18 N.
3. Select option A.
Answer: (A) | mechanics |
Voltage is 25 V. | {
"A": "20 V",
"B": "30 V",
"C": "35 V",
"D": "25 V"
} | phy_0464 | multiple_choice | en | A current of 5 A flows through 5 Ω. What is the voltage? | [
"V = 5 A × 5 Ω.",
"V = 25 V.",
"Select option D."
] | physics | Answer: 25 V
Steps:
1. V = 5 A × 5 Ω.
2. V = 25 V.
3. Select option D.
Answer: (D) | electromagnetism |
Heat: 75348 J. | null | phy_0465 | worked_example | en | How much heat warms 2 kg of water by 9 K? (c = 4186 J/(kg·K)) | [
"Q = 2 kg × 4186 J/(kg·K) × 9 K.",
"= 75348 J."
] | physics | Answer: Heat: 75348 J.
Steps:
1. Q = 2 kg × 4186 J/(kg·K) × 9 K.
2. = 75348 J. | thermodynamics |
Time: 8.3 s. | null | phy_0466 | worked_example | en | Light travels 25×10⁸ m. Compute the travel time. (c = 3×10⁸ m/s) | [
"t = d/c.",
"t = 25×10⁸ / 3×10⁸ s.",
"= 8.3 s."
] | physics | Answer: Time: 8.3 s.
Steps:
1. t = d/c.
2. t = 25×10⁸ / 3×10⁸ s.
3. = 8.3 s. | optics |
Speed: 1950 m/s. | null | phy_0467 | worked_example | en | A string wave has f = 650 Hz and λ = 3 m. Compute its speed. | [
"v = f×λ.",
"v = 650 Hz × 3 m.",
"= 1950 m/s."
] | physics | Answer: Speed: 1950 m/s.
Steps:
1. v = f×λ.
2. v = 650 Hz × 3 m.
3. = 1950 m/s. | waves |
The answer is Superposition. | {
"A": "Superscription",
"B": "Superstition",
"C": "Superposition",
"D": "Supervision"
} | phy_0468 | multiple_choice | en | Choose: what blends till measured? | [
"One outcome picked.",
"So: Superposition.",
"Select option C."
] | physics | Answer: Superposition
Steps:
1. One outcome picked.
2. So: Superposition.
3. Select option C.
Answer: (C) | modern |
Momentum: 36 kg·m/s. | null | phy_0469 | worked_example | en | A mass of 12 kg moves at 3 m/s. Compute its momentum. | [
"p = m×v.",
"p = 12 kg × 3 m/s.",
"= 36 kg·m/s."
] | physics | Answer: Momentum: 36 kg·m/s.
Steps:
1. p = m×v.
2. p = 12 kg × 3 m/s.
3. = 36 kg·m/s. | mechanics |
Power is 72 W. | {
"A": "72 W",
"B": "60 W",
"C": "84 W",
"D": "96 W"
} | phy_0470 | multiple_choice | en | A bulb runs at 12 V drawing 6 A. What is its power? | [
"P = 12 V × 6 A.",
"P = 72 W.",
"Select option A."
] | physics | Answer: 72 W
Steps:
1. P = 12 V × 6 A.
2. P = 72 W.
3. Select option A.
Answer: (A) | electromagnetism |
Teplota je 294 K. | {
"A": "293 K",
"B": "294 K",
"C": "295 K",
"D": "296 K"
} | phy_0471 | multiple_choice | cs | Pokojová teplota je 21 °C. Kolik je to kelvinů? | [
"21 °C + 273.",
"= 294 K.",
"Vyber možnost B."
] | physics | Answer: 294 K
Steps:
1. 21 °C + 273.
2. = 294 K.
3. Vyber možnost B.
Answer: (B) | thermodynamics |
Zvětšení: 5×. | null | phy_0472 | worked_example | cs | Obraz vzniká 50 cm od čočky, předmět v 10 cm. Spočítej zvětšení. | [
"M = di/do.",
"M = 50 cm / 10 cm.",
"= 5×."
] | physics | Answer: Zvětšení: 5×.
Steps:
1. M = di/do.
2. M = 50 cm / 10 cm.
3. = 5×. | optics |
Reflected waves lock into fixed nodes, forming musical notes. | null | phy_0473 | concept | en | Why standing waves? | [
"Reflected waves lock into fixed nodes, forming musical notes.",
"So the answer stands: Reflected waves lock into fixed nodes, forming musical notes."
] | physics | Answer: Reflected waves lock into fixed nodes, forming musical notes.
Steps:
1. Reflected waves lock into fixed nodes, forming musical notes.
2. So the answer stands: Reflected waves lock into fixed nodes, forming musical notes. | waves |
Nukleonové číslo: 9. | null | phy_0474 | worked_example | cs | Jádro má 4 protonů a 5 neutronů. Spočítej jeho nukleonové číslo. | [
"A = Z+N.",
"A = 4 + 5.",
"= 9."
] | physics | Answer: Nukleonové číslo: 9.
Steps:
1. A = Z+N.
2. A = 4 + 5.
3. = 9. | modern |
Speed is 14 m/s. | {
"A": "13 m/s",
"B": "14 m/s",
"C": "15 m/s",
"D": "16 m/s"
} | phy_0475 | multiple_choice | en | A car travels 140 m in 10 s. What is its speed? | [
"v = 140 m / 10 s.",
"v = 14 m/s.",
"Select option B."
] | physics | Answer: 14 m/s
Steps:
1. v = 140 m / 10 s.
2. v = 14 m/s.
3. Select option B.
Answer: (B) | mechanics |
Voltage: 108 V. | null | phy_0476 | worked_example | en | A current of 9 A flows through 12 Ω. Compute the voltage. | [
"V = I×R.",
"V = 9 A × 12 Ω.",
"= 108 V."
] | physics | Answer: Voltage: 108 V.
Steps:
1. V = I×R.
2. V = 9 A × 12 Ω.
3. = 108 V. | electromagnetism |
One mole holds 6.02e23 particles, bridging atoms to grams. | null | phy_0477 | concept | en | Why Avogadro's number? | [
"One mole holds 6.02e23 particles, bridging atoms to grams.",
"So the answer stands: One mole holds 6.02e23 particles, bridging atoms to grams."
] | physics | Answer: One mole holds 6.02e23 particles, bridging atoms to grams.
Steps:
1. One mole holds 6.02e23 particles, bridging atoms to grams.
2. So the answer stands: One mole holds 6.02e23 particles, bridging atoms to grams. | thermodynamics |
Apparent depth: 100 cm. | null | phy_0478 | worked_example | en | An object sits 150 cm deep in glass (n = 1.5). Compute the apparent depth. | [
"d' = d/n.",
"d' = 150 cm / 1.5.",
"= 100 cm."
] | physics | Answer: Apparent depth: 100 cm.
Steps:
1. d' = d/n.
2. d' = 150 cm / 1.5.
3. = 100 cm. | optics |
Integer multiples of the fundamental ring together, colouring timbre. | null | phy_0479 | concept | en | What are harmonics? | [
"Integer multiples of the fundamental ring together, colouring timbre.",
"So the answer stands: Integer multiples of the fundamental ring together, colouring timbre."
] | physics | Answer: Integer multiples of the fundamental ring together, colouring timbre.
Steps:
1. Integer multiples of the fundamental ring together, colouring timbre.
2. So the answer stands: Integer multiples of the fundamental ring together, colouring timbre. | waves |
Stimulated emission clones photons identically, a pure quantum device. | null | phy_0480 | concept | en | Why lasers quantum? | [
"Stimulated emission clones photons identically, a pure quantum device.",
"So the answer stands: Stimulated emission clones photons identically, a pure quantum device."
] | physics | Answer: Stimulated emission clones photons identically, a pure quantum device.
Steps:
1. Stimulated emission clones photons identically, a pure quantum device.
2. So the answer stands: Stimulated emission clones photons identically, a pure quantum device. | modern |
Net force: 22 N. | null | phy_0481 | worked_example | en | A mass of 11 kg accelerates at 2 m/s². Compute the net force. | [
"F = m×a.",
"F = 11 kg × 2 m/s².",
"= 22 N."
] | physics | Answer: Net force: 22 N.
Steps:
1. F = m×a.
2. F = 11 kg × 2 m/s².
3. = 22 N. | mechanics |
Impedance extends resistance to AC with phase, combining R, L, and C. | null | phy_0482 | concept | en | What is impedance? | [
"Impedance extends resistance to AC with phase, combining R, L, and C.",
"So the answer stands: Impedance extends resistance to AC with phase, combining R, L, and C."
] | physics | Answer: Impedance extends resistance to AC with phase, combining R, L, and C.
Steps:
1. Impedance extends resistance to AC with phase, combining R, L, and C.
2. So the answer stands: Impedance extends resistance to AC with phase, combining R, L, and C. | electromagnetism |
Power: 130 W. | null | phy_0483 | worked_example | en | An engine does 1300 J of work in 10 s. Compute its power. | [
"P = W/t.",
"P = 1300 J / 10 s.",
"= 130 W."
] | physics | Answer: Power: 130 W.
Steps:
1. P = W/t.
2. P = 1300 J / 10 s.
3. = 130 W. | thermodynamics |
Magnification: 11×. | null | phy_0484 | worked_example | en | An image forms 110 cm from a lens, object at 10 cm. Compute the magnification. | [
"M = di/do.",
"M = 110 cm / 10 cm.",
"= 11×."
] | physics | Answer: Magnification: 11×.
Steps:
1. M = di/do.
2. M = 110 cm / 10 cm.
3. = 11×. | optics |
Near frequencies alternate loud and soft at their difference rate. | null | phy_0485 | concept | en | Why beats? | [
"Near frequencies alternate loud and soft at their difference rate.",
"So the answer stands: Near frequencies alternate loud and soft at their difference rate."
] | physics | Answer: Near frequencies alternate loud and soft at their difference rate.
Steps:
1. Near frequencies alternate loud and soft at their difference rate.
2. So the answer stands: Near frequencies alternate loud and soft at their difference rate. | waves |
Survivors: 2000. | null | phy_0486 | worked_example | en | A sample of 8000 atoms undergoes 2 half-lives. Compute the survivors. | [
"Halve: 8000 → 4000.",
"Halve: 4000 → 2000.",
"= 2000."
] | physics | Answer: Survivors: 2000.
Steps:
1. Halve: 8000 → 4000.
2. Halve: 4000 → 2000.
3. = 2000. | modern |
Isolated total energy never changes form-sum, so accounting always balances. | null | phy_0487 | concept | en | Why conserve energy? | [
"Isolated total energy never changes form-sum, so accounting always balances.",
"So the answer stands: Isolated total energy never changes form-sum, so accounting always balances."
] | physics | Answer: Isolated total energy never changes form-sum, so accounting always balances.
Steps:
1. Isolated total energy never changes form-sum, so accounting always balances.
2. So the answer stands: Isolated total energy never changes form-sum, so accounting always balances. | mechanics |
Charge is 100 C. | {
"A": "80 C",
"B": "100 C",
"C": "120 C",
"D": "140 C"
} | phy_0488 | multiple_choice | en | A current of 4 A flows for 25 s. How much charge passes? | [
"Q = 4 A × 25 s.",
"Q = 100 C.",
"Select option B."
] | physics | Answer: 100 C
Steps:
1. Q = 4 A × 25 s.
2. Q = 100 C.
3. Select option B.
Answer: (B) | electromagnetism |
Temperature: 297 K. | null | phy_0489 | worked_example | en | Temperature is 24 °C. Convert it to kelvin. | [
"Add 273.",
"24 + 273.",
"= 297 K."
] | physics | Answer: Temperature: 297 K.
Steps:
1. Add 273.
2. 24 + 273.
3. = 297 K. | thermodynamics |
Magnification is 6×. | {
"A": "6×",
"B": "5×",
"C": "7×",
"D": "8×"
} | phy_0490 | multiple_choice | en | An image forms 60 cm from a lens, object at 10 cm. What is the magnification? | [
"M = 60 cm / 10 cm.",
"M = 6×.",
"Select option A."
] | physics | Answer: 6×
Steps:
1. M = 60 cm / 10 cm.
2. M = 6×.
3. Select option A.
Answer: (A) | optics |
Log loudness scale where +10 dB means ten times the power. | null | phy_0491 | concept | en | What is the decibel? | [
"Log loudness scale where +10 dB means ten times the power.",
"So the answer stands: Log loudness scale where +10 dB means ten times the power."
] | physics | Answer: Log loudness scale where +10 dB means ten times the power.
Steps:
1. Log loudness scale where +10 dB means ten times the power.
2. So the answer stands: Log loudness scale where +10 dB means ten times the power. | waves |
Lines: 78. | null | phy_0492 | worked_example | en | An atom is excited to level n = 13. Count the spectral lines it can emit. | [
"Pairs: 13×12/2.",
"= 156/2.",
"= 78."
] | physics | Answer: Lines: 78.
Steps:
1. Pairs: 13×12/2.
2. = 156/2.
3. = 78. | modern |
Power is energy per time in watts, rating how fast work gets done. | null | phy_0493 | concept | en | What is power? | [
"Power is energy per time in watts, rating how fast work gets done.",
"So the answer stands: Power is energy per time in watts, rating how fast work gets done."
] | physics | Answer: Power is energy per time in watts, rating how fast work gets done.
Steps:
1. Power is energy per time in watts, rating how fast work gets done.
2. So the answer stands: Power is energy per time in watts, rating how fast work gets done. | mechanics |
Energy: 1300 J. | null | phy_0494 | worked_example | en | A 100 W heater runs for 13 s. Compute the energy used. | [
"E = P×t.",
"E = 100 W × 13 s.",
"= 1300 J."
] | physics | Answer: Energy: 1300 J.
Steps:
1. E = P×t.
2. E = 100 W × 13 s.
3. = 1300 J. | electromagnetism |
Zachování energie pro teplo a práci. | null | phy_0495 | concept | cs | Co je první zákon? | [
"Zachování energie pro teplo a práci.",
"Odpověď tedy platí: Zachování energie pro teplo a práci."
] | physics | Answer: Zachování energie pro teplo a práci.
Steps:
1. Zachování energie pro teplo a práci.
2. Odpověď tedy platí: Zachování energie pro teplo a práci. | thermodynamics |
Čas: 3,3 s. | null | phy_0496 | worked_example | cs | Světlo letí 10×10⁸ m. Spočítej dobu letu. (c = 3×10⁸ m/s) | [
"t = d/c.",
"t = 10×10⁸ / 3×10⁸ s.",
"= 3,3 s."
] | physics | Answer: Čas: 3,3 s.
Steps:
1. t = d/c.
2. t = 10×10⁸ / 3×10⁸ s.
3. = 3,3 s. | optics |
Rychlost: 900 m/s. | null | phy_0497 | worked_example | cs | Vlna na struně má f = 300 Hz a λ = 3 m. Spočítej její rychlost. | [
"v = f×λ.",
"v = 300 Hz × 3 m.",
"= 900 m/s."
] | physics | Answer: Rychlost: 900 m/s.
Steps:
1. v = f×λ.
2. v = 300 Hz × 3 m.
3. = 900 m/s. | waves |
Hmota stlačená za horizontem chytí i světlo. | null | phy_0498 | concept | cs | Co je černá díra? | [
"Hmota stlačená za horizontem chytí i světlo.",
"Odpověď tedy platí: Hmota stlačená za horizontem chytí i světlo."
] | physics | Answer: Hmota stlačená za horizontem chytí i světlo.
Steps:
1. Hmota stlačená za horizontem chytí i světlo.
2. Odpověď tedy platí: Hmota stlačená za horizontem chytí i světlo. | modern |
Work: 200 J. | null | phy_0499 | worked_example | en | A force of 50 N pushes 4 m. Compute the work done. | [
"W = F×d.",
"W = 50 N × 4 m.",
"= 200 J."
] | physics | Answer: Work: 200 J.
Steps:
1. W = F×d.
2. W = 50 N × 4 m.
3. = 200 J. | mechanics |
Energie: 700 J. | null | phy_0500 | worked_example | cs | Topidlo 100 W běží po 7 s. Spočítej spotřebovanou energii. | [
"E = P×t.",
"E = 100 W × 7 s.",
"= 700 J."
] | physics | Answer: Energie: 700 J.
Steps:
1. E = P×t.
2. E = 100 W × 7 s.
3. = 700 J. | electromagnetism |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.