Q. In an AC circuit, if the voltage is given by V(t) = V_0 sin(ωt), what is the expression for the current if the circuit is purely inductive? (2023)
A.
I(t) = I_0 sin(ωt)
B.
I(t) = I_0 sin(ωt - π/2)
C.
I(t) = I_0 cos(ωt)
D.
I(t) = I_0 cos(ωt + π/2)
Show solution
Solution
In a purely inductive circuit, the current lags the voltage by 90 degrees (or π/2 radians). Therefore, I(t) = I_0 sin(ωt - π/2).
Correct Answer:
B
— I(t) = I_0 sin(ωt - π/2)
Learn More →
Q. In an AC circuit, if the voltage is given by V(t) = V₀ sin(ωt), what is the expression for the current through a capacitor? (2022)
A.
I(t) = C dV/dt
B.
I(t) = V₀ sin(ωt)
C.
I(t) = V₀ cos(ωt)
D.
I(t) = V₀ sin(ωt)/R
Show solution
Solution
The current through a capacitor is given by I(t) = C dV/dt. For V(t) = V₀ sin(ωt), the current can be derived from this expression.
Correct Answer:
A
— I(t) = C dV/dt
Learn More →
Q. In an AC circuit, if the voltage is V(t) = 120 sin(ωt), what is the RMS voltage? (2017)
A.
120 V
B.
60 V
C.
84.85 V
D.
100 V
Show solution
Solution
RMS voltage V_rms = V_peak / √2 = 120 / √2 = 84.85 V.
Correct Answer:
C
— 84.85 V
Learn More →
Q. In an AC circuit, the average power consumed is given by which formula? (2022)
A.
P = VI
B.
P = VI cos(φ)
C.
P = V²/R
D.
P = I²R
Show solution
Solution
The average power (P) consumed in an AC circuit is given by P = VI cos(φ), where φ is the phase angle between voltage and current.
Correct Answer:
B
— P = VI cos(φ)
Learn More →
Q. In an AC circuit, the current lags behind the voltage by 90 degrees in which component? (2020)
A.
Resistor
B.
Capacitor
C.
Inductor
D.
Transformer
Show solution
Solution
In an inductor, the current lags behind the voltage by 90 degrees.
Correct Answer:
C
— Inductor
Learn More →
Q. In an AC circuit, the current lags behind the voltage by 90 degrees in which type of circuit? (2020)
A.
Resistive
B.
Inductive
C.
Capacitive
D.
RLC
Show solution
Solution
In an inductive circuit, the current lags behind the voltage by 90 degrees.
Correct Answer:
B
— Inductive
Learn More →
Q. In an AC circuit, the current lags the voltage by 90 degrees in which of the following components? (2020)
A.
Resistor
B.
Capacitor
C.
Inductor
D.
Transformer
Show solution
Solution
In an inductor, the current lags the voltage by 90 degrees.
Correct Answer:
C
— Inductor
Learn More →
Q. In an AC circuit, the current lags the voltage by 90 degrees in which type of circuit? (2020)
A.
Resistive
B.
Capacitive
C.
Inductive
D.
RLC
Show solution
Solution
In an inductive circuit, the current lags the voltage by 90 degrees.
Correct Answer:
C
— Inductive
Learn More →
Q. In an AC circuit, the voltage is given by V(t) = V0 sin(ωt). What is the peak voltage? (2021)
Show solution
Solution
The peak voltage in the equation V(t) = V0 sin(ωt) is V0.
Correct Answer:
A
— V0
Learn More →
Q. In an AC circuit, the voltage is given by V(t) = V0 sin(ωt). What is the peak voltage if V0 = 10V? (2021)
A.
5V
B.
10V
C.
15V
D.
20V
Show solution
Solution
The peak voltage V0 is given directly in the equation as 10V.
Correct Answer:
B
— 10V
Learn More →
Q. In an AC circuit, what is the phase difference between voltage and current in a purely inductive circuit? (2021)
A.
0 degrees
B.
90 degrees
C.
180 degrees
D.
270 degrees
Show solution
Solution
In a purely inductive AC circuit, the current lags the voltage by 90 degrees.
Correct Answer:
B
— 90 degrees
Learn More →
Q. In an AC circuit, what is the relationship between the average power and the RMS voltage? (2023)
A.
P = V_rms²/R
B.
P = V_peak²/R
C.
P = V_rms/R
D.
P = V_peak/R
Show solution
Solution
The average power (P) in an AC circuit is given by P = V_rms²/R, where R is the resistance.
Correct Answer:
A
— P = V_rms²/R
Learn More →
Q. In an AC circuit, what is the unit of reactance? (2019)
A.
Ohm
B.
Farad
C.
Henry
D.
Volt
Show solution
Solution
Reactance is measured in Ohms, just like resistance.
Correct Answer:
A
— Ohm
Learn More →
Q. In an AC generator, the induced EMF is maximum when the coil is positioned at what angle to the magnetic field?
A.
0 degrees
B.
45 degrees
C.
90 degrees
D.
180 degrees
Show solution
Solution
In an AC generator, the induced EMF is maximum when the coil is positioned at 90 degrees to the magnetic field, as this is when the rate of change of magnetic flux is greatest.
Correct Answer:
C
— 90 degrees
Learn More →
Q. In an adiabatic process, the relationship between pressure and volume for an ideal gas is given by which equation? (2020)
A.
PV^n = constant
B.
PV = nRT
C.
P1V1 = P2V2
D.
V/T = constant
Show solution
Solution
In an adiabatic process, the relationship is given by PV^n = constant, where n is the heat capacity ratio.
Correct Answer:
A
— PV^n = constant
Learn More →
Q. In an adiabatic process, the temperature of an ideal gas decreases. What happens to its pressure?
A.
Increases
B.
Decreases
C.
Remains constant
D.
Depends on volume
Show solution
Solution
In an adiabatic process, as the temperature decreases, the pressure also decreases due to the ideal gas law.
Correct Answer:
B
— Decreases
Learn More →
Q. In an adiabatic process, which of the following is true? (2020)
A.
Heat is absorbed from the surroundings
B.
Heat is released to the surroundings
C.
No heat is exchanged
D.
Temperature remains constant
Show solution
Solution
In an adiabatic process, there is no heat exchange with the surroundings, meaning no heat is absorbed or released.
Correct Answer:
C
— No heat is exchanged
Learn More →
Q. In an adiabatic process, which of the following remains constant? (2020)
A.
Temperature
B.
Pressure
C.
Internal Energy
D.
Enthalpy
Show solution
Solution
In an adiabatic process, there is no heat exchange, so the internal energy remains constant for an ideal gas.
Correct Answer:
C
— Internal Energy
Learn More →
Q. In an ecosystem, which of the following organisms is known as a primary consumer? (2019)
A.
Herbivores
B.
Carnivores
C.
Decomposers
D.
Producers
Show solution
Solution
Herbivores are primary consumers as they feed directly on producers (plants).
Correct Answer:
A
— Herbivores
Learn More →
Q. In an ecosystem, which of the following organisms is known as a primary producer? (2021)
A.
Herbivores
B.
Carnivores
C.
Decomposers
D.
Plants
Show solution
Solution
Plants are primary producers as they convert sunlight into chemical energy through photosynthesis.
Correct Answer:
D
— Plants
Learn More →
Q. In an electrochemical cell, the anode is where: (2019)
A.
Oxidation occurs
B.
Reduction occurs
C.
Electrons are gained
D.
Ions are produced
Show solution
Solution
In an electrochemical cell, oxidation occurs at the anode.
Correct Answer:
A
— Oxidation occurs
Learn More →
Q. In an isochoric process, what remains constant? (2021)
A.
Pressure
B.
Volume
C.
Temperature
D.
Heat
Show solution
Solution
In an isochoric process, the volume of the system remains constant.
Correct Answer:
B
— Volume
Learn More →
Q. In an isochoric process, which of the following remains constant? (2022)
A.
Pressure
B.
Volume
C.
Temperature
D.
Internal Energy
Show solution
Solution
In an isochoric process, the volume remains constant.
Correct Answer:
B
— Volume
Learn More →
Q. In an isothermal process, the temperature of an ideal gas remains constant. If the volume of the gas is doubled, what happens to the pressure? (2020)
A.
It doubles
B.
It halves
C.
It remains constant
D.
It quadruples
Show solution
Solution
According to Boyle's Law, P1V1 = P2V2. If V2 = 2V1, then P2 = P1/2.
Correct Answer:
B
— It halves
Learn More →
Q. In an isothermal process, the temperature of the gas remains constant. What can be said about the internal energy of an ideal gas? (2020) 2020
A.
It increases
B.
It decreases
C.
It remains constant
D.
It varies with pressure
Show solution
Solution
For an ideal gas, the internal energy depends only on temperature. Since the temperature remains constant in an isothermal process, the internal energy also remains constant.
Correct Answer:
C
— It remains constant
Learn More →
Q. In an isothermal process, the temperature of the system remains: (2023)
A.
Constant
B.
Increases
C.
Decreases
D.
Varies
Show solution
Solution
In an isothermal process, the temperature of the system remains constant.
Correct Answer:
A
— Constant
Learn More →
Q. In an RLC circuit, if the inductive reactance is 10Ω and capacitive reactance is 5Ω, what is the net reactance? (2020)
A.
5Ω
B.
10Ω
C.
15Ω
D.
0Ω
Show solution
Solution
Net reactance = XL - XC = 10Ω - 5Ω = 5Ω.
Correct Answer:
A
— 5Ω
Learn More →
Q. In an RLC circuit, if the inductive reactance is 30Ω and capacitive reactance is 20Ω, what is the net reactance? (2020)
A.
10Ω
B.
50Ω
C.
30Ω
D.
20Ω
Show solution
Solution
Net reactance X = XL - XC = 30Ω - 20Ω = 10Ω.
Correct Answer:
A
— 10Ω
Learn More →
Q. In an RLC circuit, if the resistance is 10Ω, the inductance is 0.1H, and the capacitance is 20μF, what is the total impedance at 50Hz? (2022)
A.
10Ω
B.
15.81Ω
C.
20Ω
D.
25Ω
Show solution
Solution
Calculate XL = 2πfL = 31.42Ω and XC = 1/(2πfC) = 159.15Ω. Z = √(R² + (XL - XC)²) = √(10² + (31.42 - 159.15)²) = 15.81Ω.
Correct Answer:
B
— 15.81Ω
Learn More →
Q. In an RLC circuit, if the resistance is 6Ω, inductive reactance is 8Ω, and capacitive reactance is 4Ω, what is the total impedance? (2021)
A.
10Ω
B.
12Ω
C.
14Ω
D.
16Ω
Show solution
Solution
Total impedance Z = √(R² + (XL - XC)²) = √(6² + (8 - 4)²) = √(36 + 16) = √52 ≈ 10Ω.
Correct Answer:
B
— 12Ω
Learn More →
Showing 1711 to 1740 of 5509 (184 Pages)