answer
string
choices
dict
id
string
kind
string
lang
string
question
string
steps
list
subject
string
text
string
topic
string
The net moment is 1100 N·m clockwise.
null
eng_0151
worked_example
en
500 N at 4 m clockwise, 300 N at 3 m counter-clockwise. What is the net moment?
[ "M1 = 500×4 = 2000 N·m.", "M2 = 300×3 = 900 N·m.", "Net 1100 N·m." ]
engineering
Answer: 1100 N·m. Steps: 1. M1 = 500×4 = 2000 N·m. 2. M2 = 300×3 = 900 N·m. 3. Net 1100 N·m.
statics
Entropy measures energy dispersal and disorder, rising in irreversible processes.
null
eng_0152
concept
en
What is entropy?
[ "Joules per K.", "Always grows.", "Limits engines." ]
engineering
Answer: Dispersal measure. Steps: 1. Joules per K. 2. Always grows. 3. Limits engines.
thermodynamics
The stored charge is 6000 μC.
null
eng_0153
worked_example
en
Capacitor 600 μF charged to 10 V. What charge is stored?
[ "C = 600 μF, V = 10 V.", "Q = CV = 6000 μC.", "Result 6000 μC." ]
engineering
Answer: 6000 μC. Steps: 1. C = 600 μF, V = 10 V. 2. Q = CV = 6000 μC. 3. Result 6000 μC.
circuits
A time constant is the time to reach 63 percent of a step response.
null
eng_0154
concept
en
What is a time constant?
[ "Tau in s.", "One tau mark.", "Speed gauge." ]
engineering
Answer: 63 percent time. Steps: 1. Tau in s. 2. One tau mark. 3. Speed gauge.
control
Hydrostatický tlak roste s hloubkou jako ró gé há.
null
eng_0155
concept
cs
Co je hydrostatický tlak?
[ "Hloubka v m.", "Krát ró gé.", "kPa rozdíl." ]
engineering
Answer: Ró gé há. Steps: 1. Hloubka v m. 2. Krát ró gé. 3. kPa rozdíl.
fluids
The strain is 700 microstrain.
{ "A": "600 microstrain", "B": "800 microstrain", "C": "700 microstrain", "D": "900 microstrain" }
eng_0156
multiple_choice
en
Bar 1000 mm stretches 0.7 mm. What is the strain?
[ "ΔL = 0.7 mm, L = 1000 mm.", "ε = 700 microstrain.", "Select option C (700 microstrain)." ]
engineering
Answer: 700 microstrain. Steps: 1. ΔL = 0.7 mm, L = 1000 mm. 2. ε = 700 microstrain. 3. Select option C (700 microstrain). Answer: (C)
materials
Equilibrium needs zero net force and zero net moment on a body.
null
eng_0157
concept
en
What are equilibrium conditions?
[ "Sum Fx zero.", "Sum Fy zero.", "Sum M zero." ]
engineering
Answer: Zero force and moment. Steps: 1. Sum Fx zero. 2. Sum Fy zero. 3. Sum M zero.
statics
The ideal gas law links pressure, volume, and temperature as pV equals nRT.
null
eng_0158
concept
en
What is the ideal gas law?
[ "p in Pa.", "V in m³.", "T in K." ]
engineering
Answer: pV equals nRT. Steps: 1. p in Pa. 2. V in m³. 3. T in K.
thermodynamics
The power lost is 240 W.
null
eng_0159
worked_example
en
Current 2 A through 60 Ω. What power is lost?
[ "I = 2 A, R = 60 Ω.", "P = I²R = 240 W.", "Result 240 W." ]
engineering
Answer: 240 W. Steps: 1. I = 2 A, R = 60 Ω. 2. P = I²R = 240 W. 3. Result 240 W.
circuits
The D output is 20 V.
null
eng_0160
worked_example
en
Error jumps 0 to 100 units in 2 s with Kd = 0.4 s. What is the D output?
[ "Slope = 100/2 units/s.", "u = 0.4×slope = 20 V.", "Result 20 V." ]
engineering
Answer: 20 V. Steps: 1. Slope = 100/2 units/s. 2. u = 0.4×slope = 20 V. 3. Result 20 V.
control
The exit velocity is 10 m/s.
null
eng_0161
worked_example
en
Tank head 5 m (take g = 10 m/s²). What is the Torricelli velocity?
[ "h = 5 m, g = 10 m/s².", "v = √(2gh) = 10 m/s.", "Result 10 m/s." ]
engineering
Answer: 10 m/s. Steps: 1. h = 5 m, g = 10 m/s². 2. v = √(2gh) = 10 m/s. 3. Result 10 m/s.
fluids
Transverse strain is -1140 microstrain.
null
eng_0162
worked_example
en
Bar stretches 3800 microstrain, Poisson ratio 0.3. What is transverse strain?
[ "εa = 3800 microstrain, ν = 0.3.", "εt = −νεa = -1140 microstrain.", "Result -1140 microstrain." ]
engineering
Answer: -1140 microstrain. Steps: 1. εa = 3800 microstrain, ν = 0.3. 2. εt = −νεa = -1140 microstrain. 3. Result -1140 microstrain.
materials
A moment is force times perpendicular distance, tending to rotate, in newton metres.
null
eng_0163
concept
en
What is a moment?
[ "Force in N.", "Arm in m.", "M in N·m." ]
engineering
Answer: Force times distance. Steps: 1. Force in N. 2. Arm in m. 3. M in N·m.
statics
The temperature is 147 °C.
null
eng_0164
worked_example
en
Temperature is 420 K. What is it in Celsius?
[ "T = 420 K.", "C = 420 − 273 = 147 °C.", "Result 147 °C." ]
engineering
Answer: 147 °C. Steps: 1. T = 420 K. 2. C = 420 − 273 = 147 °C. 3. Result 147 °C.
thermodynamics
Proud je 14 A.
null
eng_0165
worked_example
cs
Napětí 84 V na 6 Ω. Jaký je proud?
[ "V = 84 V, R = 6 Ω.", "I = V/R = 14 A.", "Result 14 A." ]
engineering
Answer: 14 A. Steps: 1. V = 84 V, R = 6 Ω. 2. I = V/R = 14 A. 3. Result 14 A.
circuits
The total gain is 24.
{ "A": "22 (dimensionless)", "B": "24 (dimensionless)", "C": "26 (dimensionless)", "D": "28 (dimensionless)" }
eng_0166
multiple_choice
en
Two series blocks have gains 2 and 12. What is the total gain?
[ "K1 = 2, K2 = 12 (dimensionless).", "K = 24 (dimensionless).", "Select option B (24 (dimensionless))." ]
engineering
Answer: 24 (dimensionless). Steps: 1. K1 = 2, K2 = 12 (dimensionless). 2. K = 24 (dimensionless). 3. Select option B (24 (dimensionless)). Answer: (B)
control
The Reynolds number is the dimensionless ratio of inertial to viscous forces.
null
eng_0167
concept
en
What is the Reynolds number?
[ "Rho v D.", "Over mu.", "Below 2300 calm." ]
engineering
Answer: Inertia over viscous. Steps: 1. Rho v D. 2. Over mu. 3. Below 2300 calm.
fluids
Estimated strength is 1400 MPa.
null
eng_0168
worked_example
en
Steel hardness 400 HB. Estimate tensile strength (UTS ≈ 3.5·HB).
[ "Hardness = 400 HB.", "UTS ≈ 3.5×400 = 1400 MPa.", "Result 1400 MPa." ]
engineering
Answer: 1400 MPa. Steps: 1. Hardness = 400 HB. 2. UTS ≈ 3.5×400 = 1400 MPa. 3. Result 1400 MPa.
materials
The moment arm is 26 m.
null
eng_0169
worked_example
en
Moment 3900 N·m comes from 150 N force. What is the moment arm?
[ "M = 3900 N·m, F = 150 N.", "d = M/F = 26 m.", "Result 26 m." ]
engineering
Answer: 26 m. Steps: 1. M = 3900 N·m, F = 150 N. 2. d = M/F = 26 m. 3. Result 26 m.
statics
The temperature is 343 K.
{ "A": "338 K", "B": "348 K", "C": "343 K", "D": "353 K" }
eng_0170
multiple_choice
en
Temperature is 70 °C. What is it in kelvin?
[ "T = 70 °C.", "K = 70 + 273 = 343 K.", "Select option C (343 K)." ]
engineering
Answer: 343 K. Steps: 1. T = 70 °C. 2. K = 70 + 273 = 343 K. 3. Select option C (343 K). Answer: (C)
thermodynamics
Total resistance is 1500 Ω.
{ "A": "1500 Ω", "B": "1400 Ω", "C": "1600 Ω", "D": "1550 Ω" }
eng_0171
multiple_choice
en
Resistors 100 Ω and 1400 Ω in series. What is total resistance?
[ "R1 = 100 Ω, R2 = 1400 Ω.", "R = 1500 Ω.", "Select option A (1500 Ω)." ]
engineering
Answer: 1500 Ω. Steps: 1. R1 = 100 Ω, R2 = 1400 Ω. 2. R = 1500 Ω. 3. Select option A (1500 Ω). Answer: (A)
circuits
The closed-loop gain is 0.9.
null
eng_0172
worked_example
en
Unity feedback loop, forward gain 9. What is the closed-loop gain?
[ "K = 9 (dimensionless).", "T = K/(1+K) = 0.9 (dimensionless).", "Result 0.9 (dimensionless)." ]
engineering
Answer: 0.9 (dimensionless). Steps: 1. K = 9 (dimensionless). 2. T = K/(1+K) = 0.9 (dimensionless). 3. Result 0.9 (dimensionless).
control
The mass flow is 10 kg/s.
null
eng_0173
worked_example
en
Water flows 10 L/s. What is the mass flow in kg/s?
[ "Q = 10 L/s, ρ = 1000 kg/m³.", "ṁ = 10 kg/s.", "Result 10 kg/s." ]
engineering
Answer: 10 kg/s. Steps: 1. Q = 10 L/s, ρ = 1000 kg/m³. 2. ṁ = 10 kg/s. 3. Result 10 kg/s.
fluids
The stress is 90 MPa.
{ "A": "80 MPa", "B": "100 MPa", "C": "110 MPa", "D": "90 MPa" }
eng_0174
multiple_choice
en
Steel (E = 200 GPa) at strain 450 microstrain. What is the stress?
[ "E = 200 GPa, ε = 450 microstrain.", "σ = Eε = 90 MPa.", "Select option D (90 MPa)." ]
engineering
Answer: 90 MPa. Steps: 1. E = 200 GPa, ε = 450 microstrain. 2. σ = Eε = 90 MPa. 3. Select option D (90 MPa). Answer: (D)
materials
The horizontal component is 420 N.
null
eng_0175
worked_example
en
Force 700 N pulls at a 3-4-5 angle. What is the horizontal component?
[ "F = 700 N, cos = 3/5.", "Fx = 0.6×700 = 420 N.", "Result 420 N." ]
engineering
Answer: 420 N. Steps: 1. F = 700 N, cos = 3/5. 2. Fx = 0.6×700 = 420 N. 3. Result 420 N.
statics
Specific heat is heat per unit mass and degree, in joules per kilogram kelvin.
null
eng_0176
concept
en
What is specific heat?
[ "Mass in kg.", "Delta T in K.", "Q in J." ]
engineering
Answer: Heat per kg K. Steps: 1. Mass in kg. 2. Delta T in K. 3. Q in J.
thermodynamics
Parallel resistors combine by reciprocal sum, lowering total resistance.
null
eng_0177
concept
en
How do parallel resistors combine?
[ "Same voltage.", "Currents split.", "R drops." ]
engineering
Answer: Reciprocal sum. Steps: 1. Same voltage. 2. Currents split. 3. R drops.
circuits
Settling time is how long output takes to stay within an error band.
null
eng_0178
concept
en
What is settling time?
[ "2 percent band.", "About 4 tau.", "Wait done." ]
engineering
Answer: Stay in band. Steps: 1. 2 percent band. 2. About 4 tau. 3. Wait done.
control
Gauge pressure is 117.72 kPa.
{ "A": "112.72 kPa", "B": "122.72 kPa", "C": "117.72 kPa", "D": "127.72 kPa" }
eng_0179
multiple_choice
en
Water depth is 12 m. What is gauge pressure?
[ "ρ = 1000 kg/m³, h = 12 m.", "p = ρgh = 117.72 kPa.", "Select option C (117.72 kPa)." ]
engineering
Answer: 117.72 kPa. Steps: 1. ρ = 1000 kg/m³, h = 12 m. 2. p = ρgh = 117.72 kPa. 3. Select option C (117.72 kPa). Answer: (C)
fluids
Hookeův zákon říká, že napětí je úměrné deformaci v pružné oblasti.
null
eng_0180
concept
cs
Co je Hookeův zákon?
[ "Sigma rovná E.", "Epsilon malé.", "Odtížení vrátí." ]
engineering
Answer: Napětí drží deformaci. Steps: 1. Sigma rovná E. 2. Epsilon malé. 3. Odtížení vrátí.
materials
Rovnováha žádá nulovou sílu i nulový moment na těleso.
null
eng_0181
concept
cs
Co jsou podmínky rovnováhy?
[ "Součet Fx nula.", "Součet Fy nula.", "Součet M nula." ]
engineering
Answer: Nulová síla i moment. Steps: 1. Součet Fx nula. 2. Součet Fy nula. 3. Součet M nula.
statics
The work done is 320 kJ.
{ "A": "300 kJ", "B": "340 kJ", "C": "360 kJ", "D": "320 kJ" }
eng_0182
multiple_choice
en
Gas expands at 200 kPa by 1.6 m³. What work is done?
[ "p = 200 kPa, ΔV = 1.6 m³.", "W = pΔV = 320 kJ.", "Select option D (320 kJ)." ]
engineering
Answer: 320 kJ. Steps: 1. p = 200 kPa, ΔV = 1.6 m³. 2. W = pΔV = 320 kJ. 3. Select option D (320 kJ). Answer: (D)
thermodynamics
Odpor je 17 Ω.
null
eng_0183
worked_example
cs
Napětí 51 V žene 3 A. Jaký je odpor?
[ "V = 51 V, I = 3 A.", "R = V/I = 17 Ω.", "Result 17 Ω." ]
engineering
Answer: 17 Ω. Steps: 1. V = 51 V, I = 3 A. 2. R = V/I = 17 Ω. 3. Result 17 Ω.
circuits
The steady value is 55 units.
{ "A": "50 units", "B": "60 units", "C": "55 units", "D": "65 units" }
eng_0184
multiple_choice
en
System K/(10s+1) with K = 55 gets a unit step. What is the steady value?
[ "DC gain K = 55 (dimensionless).", "Step final = 55 units.", "Select option C (55 units)." ]
engineering
Answer: 55 units. Steps: 1. DC gain K = 55 (dimensionless). 2. Step final = 55 units. 3. Select option C (55 units). Answer: (C)
control
Dynamic pressure is 1815 Pa.
null
eng_0185
worked_example
en
Air (ρ = 1.2 kg/m³) moves 55 m/s. What is the dynamic pressure?
[ "ρ = 1.2 kg/m³, v = 55 m/s.", "q = ½ρv² = 1815 Pa.", "Result 1815 Pa." ]
engineering
Answer: 1815 Pa. Steps: 1. ρ = 1.2 kg/m³, v = 55 m/s. 2. q = ½ρv² = 1815 Pa. 3. Result 1815 Pa.
fluids
Ultimate tensile strength is the maximum engineering stress before necking.
null
eng_0186
concept
en
What is ultimate tensile strength?
[ "Climb curve.", "Top breaks soon.", "MPa scale." ]
engineering
Answer: Peak stress. Steps: 1. Climb curve. 2. Top breaks soon. 3. MPa scale.
materials
The vertical component is 600 N.
null
eng_0187
worked_example
en
Force 750 N pulls at a 3-4-5 angle. What is the vertical component?
[ "F = 750 N, sin = 4/5.", "Fy = 0.8×750 = 600 N.", "Result 600 N." ]
engineering
Answer: 600 N. Steps: 1. F = 750 N, sin = 4/5. 2. Fy = 0.8×750 = 600 N. 3. Result 600 N.
statics
Carnot efficiency is 70%.
{ "A": "70%", "B": "75%", "C": "65%", "D": "80%" }
eng_0188
multiple_choice
en
Carnot engine between 300 K and 1000 K. What is its efficiency?
[ "Tc = 300 K, Th = 1000 K.", "η = 1 − 300/1000 = 70%.", "Select option A (70%)." ]
engineering
Answer: 70%. Steps: 1. Tc = 300 K, Th = 1000 K. 2. η = 1 − 300/1000 = 70%. 3. Select option A (70%). Answer: (A)
thermodynamics
The tap voltage is 19 V.
null
eng_0189
worked_example
en
Divider with two 1000 Ω resistors fed 38 V. What is the tap voltage?
[ "Vin = 38 V, halves.", "Vout = 19 V.", "Result 19 V." ]
engineering
Answer: 19 V. Steps: 1. Vin = 38 V, halves. 2. Vout = 19 V. 3. Result 19 V.
circuits
Settling time is about 52 s.
{ "A": "48 s", "B": "56 s", "C": "60 s", "D": "52 s" }
eng_0190
multiple_choice
en
First-order system has time constant 13 s. What is 2% settling time?
[ "τ = 13 s.", "ts ≈ 4τ = 52 s.", "Select option D (52 s)." ]
engineering
Answer: 52 s. Steps: 1. τ = 13 s. 2. ts ≈ 4τ = 52 s. 3. Select option D (52 s). Answer: (D)
control
Outlet velocity is 26 m/s.
{ "A": "24 m/s", "B": "28 m/s", "C": "30 m/s", "D": "26 m/s" }
eng_0191
multiple_choice
en
Pipe narrows from 0.02 m² to 0.01 m², inlet velocity 13 m/s. What is outlet velocity?
[ "A1v1 = 0.02×13 m³/s.", "v2 = 26 m/s.", "Select option D (26 m/s)." ]
engineering
Answer: 26 m/s. Steps: 1. A1v1 = 0.02×13 m³/s. 2. v2 = 26 m/s. 3. Select option D (26 m/s). Answer: (D)
fluids
Elongation is 5 mm.
{ "A": "5 mm", "B": "6 mm", "C": "4 mm", "D": "7 mm" }
eng_0192
multiple_choice
en
Force 50 kN on 2 m steel bar (A = 100 mm², E = 200 GPa). What is elongation?
[ "F = 50 kN, L = 2 m.", "ΔL = FL/AE = 5 mm.", "Select option A (5 mm)." ]
engineering
Answer: 5 mm. Steps: 1. F = 50 kN, L = 2 m. 2. ΔL = FL/AE = 5 mm. 3. Select option A (5 mm). Answer: (A)
materials
A couple is two equal opposite parallel forces giving pure moment without net force.
null
eng_0193
concept
en
What is a couple?
[ "Equal forces.", "Opposite sense.", "No net force." ]
engineering
Answer: Pure moment. Steps: 1. Equal forces. 2. Opposite sense. 3. No net force.
statics
Enthalpy is internal energy plus pressure-volume work, handy for flow processes.
null
eng_0194
concept
en
What is enthalpy?
[ "Internal plus.", "Flow work.", "kJ per kg." ]
engineering
Answer: U plus pV. Steps: 1. Internal plus. 2. Flow work. 3. kJ per kg.
thermodynamics
The equivalent is 75 Ω.
{ "A": "80 Ω", "B": "75 Ω", "C": "70 Ω", "D": "85 Ω" }
eng_0195
multiple_choice
en
Two 150 Ω resistors in parallel. What is the equivalent?
[ "R = 150 Ω each.", "Req = R/2 = 75 Ω.", "Select option B (75 Ω)." ]
engineering
Answer: 75 Ω. Steps: 1. R = 150 Ω each. 2. Req = R/2 = 75 Ω. 3. Select option B (75 Ω). Answer: (B)
circuits
Overshoot is the peak excursion past the final value in percent.
null
eng_0196
concept
en
What is overshoot?
[ "Percent peak.", "Damping sets.", "Less is calm." ]
engineering
Answer: Peak past final. Steps: 1. Percent peak. 2. Damping sets. 3. Less is calm.
control
The volume is 26 m³.
null
eng_0197
worked_example
en
Tank base area 2 m², depth 13 m. What is the water volume?
[ "A = 2 m², h = 13 m.", "V = Ah = 26 m³.", "Result 26 m³." ]
engineering
Answer: 26 m³. Steps: 1. A = 2 m², h = 13 m. 2. V = Ah = 26 m³. 3. Result 26 m³.
fluids
The factor of safety is 3.
{ "A": "3.5 (dimensionless)", "B": "3 (dimensionless)", "C": "2.5 (dimensionless)", "D": "4 (dimensionless)" }
eng_0198
multiple_choice
en
Yield 300 MPa, working stress 100 MPa. What is the factor of safety?
[ "σy = 300 MPa, σw = 100 MPa.", "n = 3 (dimensionless).", "Select option B (3 (dimensionless))." ]
engineering
Answer: 3 (dimensionless). Steps: 1. σy = 300 MPa, σw = 100 MPa. 2. n = 3 (dimensionless). 3. Select option B (3 (dimensionless)). Answer: (B)
materials
A resultant is the single force replacing a system with the same effect.
null
eng_0199
concept
en
What is a resultant force?
[ "Add vectors.", "Same effect.", "One force." ]
engineering
Answer: Single replacement. Steps: 1. Add vectors. 2. Same effect. 3. One force.
statics
The specific volume is 7 m³/kg.
null
eng_0200
worked_example
en
Gas fills 28 m³ with mass 4 kg. What is the specific volume?
[ "V = 28 m³, m = 4 kg.", "v = V/m = 7 m³/kg.", "Result 7 m³/kg." ]
engineering
Answer: 7 m³/kg. Steps: 1. V = 28 m³, m = 4 kg. 2. v = V/m = 7 m³/kg. 3. Result 7 m³/kg.
thermodynamics
Spotřeba je 1600 Wh.
{ "A": "1500 Wh", "B": "1700 Wh", "C": "1600 Wh", "D": "1650 Wh" }
eng_0201
multiple_choice
cs
Žárovka 800 W svítí 2 h. Kolik energie spotřebuje?
[ "P = 800 W, t = 2 h.", "E = Pt = 1600 Wh.", "Vyber možnost C (1600 Wh)." ]
engineering
Answer: 1600 Wh. Steps: 1. P = 800 W, t = 2 h. 2. E = Pt = 1600 Wh. 3. Vyber možnost C (1600 Wh). Answer: (C)
circuits
A transfer function is output over input in Laplace form for linear systems.
null
eng_0202
concept
en
What is a transfer function?
[ "Laplace s.", "Gain plus dynamics.", "Blocks multiply." ]
engineering
Answer: Output over input. Steps: 1. Laplace s. 2. Gain plus dynamics. 3. Blocks multiply.
control
The flow rate is 28 L/s.
{ "A": "28 L/s", "B": "26 L/s", "C": "30 L/s", "D": "32 L/s" }
eng_0203
multiple_choice
en
Pipe area 20 cm², velocity 14 m/s. What is flow in litres per second?
[ "A = 20 cm², v = 14 m/s.", "Q = Av = 28 L/s.", "Select option A (28 L/s)." ]
engineering
Answer: 28 L/s. Steps: 1. A = 20 cm², v = 14 m/s. 2. Q = Av = 28 L/s. 3. Select option A (28 L/s). Answer: (A)
fluids
The stress is 120 MPa.
{ "A": "110 MPa", "B": "130 MPa", "C": "120 MPa", "D": "140 MPa" }
eng_0204
multiple_choice
en
Tensile force 12 kN on 100 mm² bar. What is the stress?
[ "F = 12 kN, A = 100 mm².", "σ = F/A = 120 MPa.", "Select option C (120 MPa)." ]
engineering
Answer: 120 MPa. Steps: 1. F = 12 kN, A = 100 mm². 2. σ = F/A = 120 MPa. 3. Select option C (120 MPa). Answer: (C)
materials
The reaction at B is 1600 N.
null
eng_0205
worked_example
en
Beam 6 m, load 2400 N at 4 m from A. What is reaction at B?
[ "F = 2400 N, span 6 m.", "RB = 2400×4/6 = 1600 N.", "Result 1600 N." ]
engineering
Answer: 1600 N. Steps: 1. F = 2400 N, span 6 m. 2. RB = 2400×4/6 = 1600 N. 3. Result 1600 N.
statics
Potřebné teplo je 150.48 kJ.
{ "A": "160.48 kJ", "B": "150.48 kJ", "C": "140.48 kJ", "D": "170.48 kJ" }
eng_0206
multiple_choice
cs
2 kg vody se ohřejí o 18 K (c = 4,18 kJ/(kg·K)). Kolik tepla?
[ "m = 2 kg, ΔT = 18 K.", "Q = mcΔT = 150.48 kJ.", "Vyber možnost B (150.48 kJ)." ]
engineering
Answer: 150.48 kJ. Steps: 1. m = 2 kg, ΔT = 18 K. 2. Q = mcΔT = 150.48 kJ. 3. Vyber možnost B (150.48 kJ). Answer: (B)
thermodynamics
Electric power is voltage times current, measured in watts.
null
eng_0207
concept
en
What is electric power?
[ "Volts times amps.", "Watts out.", "Heat or work." ]
engineering
Answer: V times I. Steps: 1. Volts times amps. 2. Watts out. 3. Heat or work.
circuits
Steady-state error is 5%.
{ "A": "5%", "B": "7%", "C": "3%", "D": "10%" }
eng_0208
multiple_choice
en
Type-0 loop has position constant Kp = 19. What is step steady-state error?
[ "Kp = 19 (dimensionless).", "ess = 100/20 = 5%.", "Select option A (5%)." ]
engineering
Answer: 5%. Steps: 1. Kp = 19 (dimensionless). 2. ess = 100/20 = 5%. 3. Select option A (5%). Answer: (A)
control
Hydraulický výkon je 3139.2 W.
null
eng_0209
worked_example
cs
Čerpadlo zvedá 0,02 m³/s vody o 16 m. Jaký hydraulický výkon je třeba?
[ "Q = 0.02 m³/s, H = 16 m.", "P = ρgQH = 3139.2 W.", "Result 3139.2 W." ]
engineering
Answer: 3139.2 W. Steps: 1. Q = 0.02 m³/s, H = 16 m. 2. P = ρgQH = 3139.2 W. 3. Result 3139.2 W.
fluids
The mass is 133.45 kg.
null
eng_0210
worked_example
en
Steel part volume 0.017 m³ (ρ = 7850 kg/m³). What is its mass?
[ "V = 0.017 m³, ρ = 7850 kg/m³.", "m = ρV = 133.45 kg.", "Result 133.45 kg." ]
engineering
Answer: 133.45 kg. Steps: 1. V = 0.017 m³, ρ = 7850 kg/m³. 2. m = ρV = 133.45 kg. 3. Result 133.45 kg.
materials
Moment je síla krát kolmá vzdálenost, jednotka newtonmetr.
null
eng_0211
concept
cs
Co je moment síly?
[ "Síla v N.", "Rameno v m.", "Moment v N·m." ]
engineering
Answer: Síla krát rameno. Steps: 1. Síla v N. 2. Rameno v m. 3. Moment v N·m.
statics
The Carnot cycle is the ideal reversible engine setting maximum efficiency between temperatures.
null
eng_0212
concept
en
What is the Carnot cycle?
[ "Two isotherms.", "Two adiabats.", "Sets limit." ]
engineering
Answer: Ideal max engine. Steps: 1. Two isotherms. 2. Two adiabats. 3. Sets limit.
thermodynamics
The leaving current is 20 A.
null
eng_0213
worked_example
en
Currents 2 A and 18 A enter a node. What current leaves?
[ "I1 = 2 A, I2 = 18 A.", "I3 = 20 A.", "Result 20 A." ]
engineering
Answer: 20 A. Steps: 1. I1 = 2 A, I2 = 18 A. 2. I3 = 20 A. 3. Result 20 A.
circuits
The error is 65 units.
null
eng_0214
worked_example
en
Setpoint 650 units, measurement 585 units. What is the error?
[ "r = 650 units, y = 585 units.", "e = r−y = 65 units.", "Result 65 units." ]
engineering
Answer: 65 units. Steps: 1. r = 650 units, y = 585 units. 2. e = r−y = 65 units. 3. Result 65 units.
control
Archimédův zákon říká, že vztlak je tíha vytlačené kapaliny.
null
eng_0215
concept
cs
Co je Archimédův zákon?
[ "Objem ponořen.", "Krát ró gé.", "Lehké plave." ]
engineering
Answer: Tíha vytlačeného. Steps: 1. Objem ponořen. 2. Krát ró gé. 3. Lehké plave.
fluids
The strain is 1200 microstrain.
{ "A": "1100 microstrain", "B": "1300 microstrain", "C": "1400 microstrain", "D": "1200 microstrain" }
eng_0216
multiple_choice
en
Bar 1000 mm stretches 1.2 mm. What is the strain?
[ "ΔL = 1.2 mm, L = 1000 mm.", "ε = 1200 microstrain.", "Select option D (1200 microstrain)." ]
engineering
Answer: 1200 microstrain. Steps: 1. ΔL = 1.2 mm, L = 1000 mm. 2. ε = 1200 microstrain. 3. Select option D (1200 microstrain). Answer: (D)
materials
Tření je odpor proti skluzu, nejvýše mí krát normálová síla.
null
eng_0217
concept
cs
Co je tření?
[ "Normála v N.", "Mí faktor.", "Brání skluzu." ]
engineering
Answer: Mí krát normála. Steps: 1. Normála v N. 2. Mí faktor. 3. Brání skluzu.
statics
The power is 800 W.
null
eng_0218
worked_example
en
Work 8000 J is done in 10 s. What is the power?
[ "W = 8000 J, t = 10 s.", "P = W/t = 800 W.", "Result 800 W." ]
engineering
Answer: 800 W. Steps: 1. W = 8000 J, t = 10 s. 2. P = W/t = 800 W. 3. Result 800 W.
thermodynamics
Proudy vstupující do uzlu se rovnají proudům vystupujícím.
null
eng_0219
concept
cs
Co je Kirchhoffův zákon proudů?
[ "Součet v A.", "Vstup rovná výstup.", "Náboj se drží." ]
engineering
Answer: Proudy se rovnají. Steps: 1. Součet v A. 2. Vstup rovná výstup. 3. Náboj se drží.
circuits
The final value is 42 units.
null
eng_0220
worked_example
en
Gain 14 system gets a step of amplitude 3. What is the final value?
[ "K = 14 (dimensionless), step 3 units.", "Final = 3×14 = 42 units.", "Result 42 units." ]
engineering
Answer: 42 units. Steps: 1. K = 14 (dimensionless), step 3 units. 2. Final = 3×14 = 42 units. 3. Result 42 units.
control
The Reynolds number is 350000.
{ "A": "325000 (dimensionless)", "B": "350000 (dimensionless)", "C": "375000 (dimensionless)", "D": "400000 (dimensionless)" }
eng_0221
multiple_choice
en
Water at 7 m/s in 0.05 m pipe (μ = 0.001 Pa·s). What is the Reynolds number?
[ "ρ = 1000 kg/m³, v = 7 m/s, D = 0.05 m.", "Re = ρvD/μ = 350000 (dimensionless).", "Select option B (350000 (dimensionless))." ]
engineering
Answer: 350000 (dimensionless). Steps: 1. ρ = 1000 kg/m³, v = 7 m/s, D = 0.05 m. 2. Re = ρvD/μ = 350000 (dimensionless). 3. Select option B (350000 (dimensionless)). Answer: (B)
fluids
Mez kluzu je napětí, kde začíná trvalá deformace.
null
eng_0222
concept
cs
Co je mez kluzu?
[ "Pod ní pružné.", "Nad ní ohne.", "Limit návrhu." ]
engineering
Answer: Začátek plastiky. Steps: 1. Pod ní pružné. 2. Nad ní ohne. 3. Limit návrhu.
materials
Each end reaction is 1000 N.
null
eng_0223
worked_example
en
Uniform beam weighs 2000 N over 8 m. What is each end reaction?
[ "W = 2000 N, midspan 4 m.", "R = W/2 = 1000 N.", "Result 1000 N." ]
engineering
Answer: 1000 N. Steps: 1. W = 2000 N, midspan 4 m. 2. R = W/2 = 1000 N. 3. Result 1000 N.
statics
A heat engine turns heat into work between hot and cold reservoirs.
null
eng_0224
concept
en
What is a heat engine?
[ "Hot source.", "Cold sink.", "Work out." ]
engineering
Answer: Heat to work. Steps: 1. Hot source. 2. Cold sink. 3. Work out.
thermodynamics
The stored charge is 9000 μC.
null
eng_0225
worked_example
en
Capacitor 900 μF charged to 10 V. What charge is stored?
[ "C = 900 μF, V = 10 V.", "Q = CV = 9000 μC.", "Result 9000 μC." ]
engineering
Answer: 9000 μC. Steps: 1. C = 900 μF, V = 10 V. 2. Q = CV = 9000 μC. 3. Result 9000 μC.
circuits
Ustálená odchylka je trvalý rozdíl cíle a výstupu.
null
eng_0226
concept
cs
Co je ustálená odchylka?
[ "Počkej dlouho.", "Odečti offset.", "Typ určuje." ]
engineering
Answer: Trvalý rozdíl. Steps: 1. Počkej dlouho. 2. Odečti offset. 3. Typ určuje.
control
Base pressure is 166.77 kPa.
null
eng_0227
worked_example
en
Still water column 17 m high. What is pressure at the base?
[ "ρ = 1000 kg/m³, h = 17 m.", "p = ρgh = 166.77 kPa.", "Result 166.77 kPa." ]
engineering
Answer: 166.77 kPa. Steps: 1. ρ = 1000 kg/m³, h = 17 m. 2. p = ρgh = 166.77 kPa. 3. Result 166.77 kPa.
fluids
The stress is 140 MPa.
{ "A": "140 MPa", "B": "130 MPa", "C": "150 MPa", "D": "160 MPa" }
eng_0228
multiple_choice
en
Steel (E = 200 GPa) at strain 700 microstrain. What is the stress?
[ "E = 200 GPa, ε = 700 microstrain.", "σ = Eε = 140 MPa.", "Select option A (140 MPa)." ]
engineering
Answer: 140 MPa. Steps: 1. E = 200 GPa, ε = 700 microstrain. 2. σ = Eε = 140 MPa. 3. Select option A (140 MPa). Answer: (A)
materials
The balancing reaction is 900 N upward.
{ "A": "950 N", "B": "900 N", "C": "850 N", "D": "1000 N" }
eng_0229
multiple_choice
en
Downward forces 360 N and 540 N act on a beam. What upward reaction balances them?
[ "F1 = 360 N, F2 = 540 N.", "R = 360+540 = 900 N.", "Select option B (900 N)." ]
engineering
Answer: 900 N. Steps: 1. F1 = 360 N, F2 = 540 N. 2. R = 360+540 = 900 N. 3. Select option B (900 N). Answer: (B)
statics
Internal energy rises 100 kJ.
{ "A": "105 kJ", "B": "95 kJ", "C": "100 kJ", "D": "110 kJ" }
eng_0230
multiple_choice
en
System gains 190 kJ of heat and does 90 kJ of work. What is internal energy change?
[ "Q = 190 kJ, W = 90 kJ.", "ΔU = Q−W = 100 kJ.", "Select option C (100 kJ)." ]
engineering
Answer: 100 kJ. Steps: 1. Q = 190 kJ, W = 90 kJ. 2. ΔU = Q−W = 100 kJ. 3. Select option C (100 kJ). Answer: (C)
thermodynamics
The power lost is 360 W.
null
eng_0231
worked_example
en
Current 2 A through 90 Ω. What power is lost?
[ "I = 2 A, R = 90 Ω.", "P = I²R = 360 W.", "Result 360 W." ]
engineering
Answer: 360 W. Steps: 1. I = 2 A, R = 90 Ω. 2. P = I²R = 360 W. 3. Result 360 W.
circuits
Settling time is about 45 s.
null
eng_0232
worked_example
en
Time constant 15 s. What is 5% settling time?
[ "τ = 15 s.", "ts ≈ 3τ = 45 s.", "Result 45 s." ]
engineering
Answer: 45 s. Steps: 1. τ = 15 s. 2. ts ≈ 3τ = 45 s. 3. Result 45 s.
control
The exit velocity is 15 m/s.
null
eng_0233
worked_example
en
Tank head 11.25 m (take g = 10 m/s²). What is the Torricelli velocity?
[ "h = 11.25 m, g = 10 m/s².", "v = √(2gh) = 15 m/s.", "Result 15 m/s." ]
engineering
Answer: 15 m/s. Steps: 1. h = 11.25 m, g = 10 m/s². 2. v = √(2gh) = 15 m/s. 3. Result 15 m/s.
fluids
Ductile materials stretch plastically before breaking, while brittle ones snap with little strain.
null
eng_0234
concept
en
How do ductile and brittle differ?
[ "Steel stretches.", "Glass snaps.", "Elongation tells." ]
engineering
Answer: Stretch versus snap. Steps: 1. Steel stretches. 2. Glass snaps. 3. Elongation tells.
materials
A free-body diagram shows an isolated body with all acting forces and reactions.
null
eng_0235
concept
en
What is a free-body diagram?
[ "Cut free.", "Draw forces.", "Solve equilibrium." ]
engineering
Answer: Isolated body sketch. Steps: 1. Cut free. 2. Draw forces. 3. Solve equilibrium.
statics
The temperature is 368 K.
{ "A": "363 K", "B": "373 K", "C": "378 K", "D": "368 K" }
eng_0236
multiple_choice
en
Temperature is 95 °C. What is it in kelvin?
[ "T = 95 °C.", "K = 95 + 273 = 368 K.", "Select option D (368 K)." ]
engineering
Answer: 368 K. Steps: 1. T = 95 °C. 2. K = 95 + 273 = 368 K. 3. Select option D (368 K). Answer: (D)
thermodynamics
A capacitor stores charge and blocks steady direct current.
null
eng_0237
concept
en
What does a capacitor do?
[ "Plates hold Q.", "DC blocked.", "AC passes." ]
engineering
Answer: Stores charge. Steps: 1. Plates hold Q. 2. DC blocked. 3. AC passes.
circuits
Poles are transfer function roots setting speed and stability of modes.
null
eng_0238
concept
en
What are poles?
[ "Denominator zero.", "Left is stable.", "Right blows." ]
engineering
Answer: Stability roots. Steps: 1. Denominator zero. 2. Left is stable. 3. Right blows.
control
Vztlak je 156960 N.
{ "A": "147150 N", "B": "166770 N", "C": "156960 N", "D": "176580 N" }
eng_0239
multiple_choice
cs
Trup vytlačí 16 m³ vody. Jaký je vztlak?
[ "V = 16 m³, ρ = 1000 kg/m³.", "F = ρgV = 156960 N.", "Vyber možnost C (156960 N)." ]
engineering
Answer: 156960 N. Steps: 1. V = 16 m³, ρ = 1000 kg/m³. 2. F = ρgV = 156960 N. 3. Vyber možnost C (156960 N). Answer: (C)
fluids
Elongation is 7.5 mm.
{ "A": "8.5 mm", "B": "7.5 mm", "C": "6.5 mm", "D": "9.5 mm" }
eng_0240
multiple_choice
en
Force 75 kN on 2 m steel bar (A = 100 mm², E = 200 GPa). What is elongation?
[ "F = 75 kN, L = 2 m.", "ΔL = FL/AE = 7.5 mm.", "Select option B (7.5 mm)." ]
engineering
Answer: 7.5 mm. Steps: 1. F = 75 kN, L = 2 m. 2. ΔL = FL/AE = 7.5 mm. 3. Select option B (7.5 mm). Answer: (B)
materials
Coulomb friction caps at mu times normal force and opposes slipping.
null
eng_0241
concept
en
What is Coulomb friction?
[ "Normal in N.", "Mu factor.", "Opposes motion." ]
engineering
Answer: Mu times normal. Steps: 1. Normal in N. 2. Mu factor. 3. Opposes motion.
statics
The efficiency is 25%.
null
eng_0242
worked_example
en
Engine turns 250 J of 1000 J heat into work. What is the efficiency?
[ "W = 250 J, Q = 1000 J.", "η = W/Q = 25%.", "Result 25%." ]
engineering
Answer: 25%. Steps: 1. W = 250 J, Q = 1000 J. 2. η = W/Q = 25%. 3. Result 25%.
thermodynamics
The voltage is 204 V.
{ "A": "192 V", "B": "216 V", "C": "228 V", "D": "204 V" }
eng_0243
multiple_choice
en
Current 17 A flows through 12 Ω. What is the voltage?
[ "I = 17 A, R = 12 Ω.", "V = IR = 204 V.", "Select option D (204 V)." ]
engineering
Answer: 204 V. Steps: 1. I = 17 A, R = 12 Ω. 2. V = IR = 204 V. 3. Select option D (204 V). Answer: (D)
circuits
The Routh criterion tests stability from characteristic coefficients without solving.
null
eng_0244
concept
en
What is the Routh criterion?
[ "Build array.", "First column.", "Sign flips bad." ]
engineering
Answer: Table test. Steps: 1. Build array. 2. First column. 3. Sign flips bad.
control
Torricelli's law gives exit velocity as root of two g h under gravity.
null
eng_0245
concept
en
What is Torricelli's law?
[ "Head in m.", "g pulls.", "v in m/s." ]
engineering
Answer: Root two g h. Steps: 1. Head in m. 2. g pulls. 3. v in m/s.
fluids
Hardness is resistance to surface indentation, ranked by Brinell or Rockwell scales.
null
eng_0246
concept
en
What is hardness?
[ "Press indenter.", "Small dent hard.", "Wear link." ]
engineering
Answer: Dent resistance. Steps: 1. Press indenter. 2. Small dent hard. 3. Wear link.
materials
Výsledný moment je 740 N·m po směru.
null
eng_0247
worked_example
cs
500 N ve 4 m po směru, 420 N ve 3 m proti směru. Jaký je výsledný moment?
[ "M1 = 500×4 = 2000 N·m.", "M2 = 420×3 = 1260 N·m.", "Net 740 N·m." ]
engineering
Answer: 740 N·m. Steps: 1. M1 = 500×4 = 2000 N·m. 2. M2 = 420×3 = 1260 N·m. 3. Net 740 N·m.
statics
Refrigerator COP is cooling delivered per unit of work input.
null
eng_0248
concept
en
What is a refrigerator COP?
[ "Q cold.", "W in.", "Ratio counts." ]
engineering
Answer: Cooling per work. Steps: 1. Q cold. 2. W in. 3. Ratio counts.
thermodynamics
The current is 20 A.
null
eng_0249
worked_example
en
Voltage 120 V across 6 Ω. What is the current?
[ "V = 120 V, R = 6 Ω.", "I = V/R = 20 A.", "Result 20 A." ]
engineering
Answer: 20 A. Steps: 1. V = 120 V, R = 6 Ω. 2. I = V/R = 20 A. 3. Result 20 A.
circuits
A Bode plot shows gain and phase versus frequency on log scales.
null
eng_0250
concept
en
What is a Bode plot?
[ "dB magnitude.", "Degrees phase.", "Margins read." ]
engineering
Answer: Gain phase curves. Steps: 1. dB magnitude. 2. Degrees phase. 3. Margins read.
control