Physics
Q. If the radius of the Earth were to increase by 50%, what would happen to the weight of an object on its surface?
A.
It increases by 50%
B.
It increases by 25%
C.
It decreases by 25%
D.
It remains the same
Show solution
Solution
Weight is inversely proportional to the square of the radius. If radius increases by 50%, weight decreases by 25%.
Correct Answer: C — It decreases by 25%
Learn More →
Q. If the radius of the Earth were to increase while keeping its mass constant, what would happen to the value of g? (2023)
A.
g increases
B.
g decreases
C.
g remains the same
D.
g becomes zero
Show solution
Solution
If the radius increases while mass remains constant, g decreases because g = G * M / r^2.
Correct Answer: B — g decreases
Learn More →
Q. If the radius of the Earth were to increase while keeping its mass constant, what would happen to the gravitational acceleration at its surface?
A.
It increases
B.
It decreases
C.
It remains the same
D.
It becomes zero
Show solution
Solution
Gravitational acceleration g = GM/R². If R increases, g decreases.
Correct Answer: B — It decreases
Learn More →
Q. If the resistance of a conductor is doubled, what happens to the current flowing through it when the voltage remains constant? (2022)
A.
Doubles
B.
Halves
C.
Remains the same
D.
Increases by 1.5 times
Show solution
Solution
According to Ohm's law, I = V/R. If R is doubled, I will be halved.
Correct Answer: B — Halves
Learn More →
Q. If the speed of light in a vacuum is 3 x 10^8 m/s, what is its speed in water (n = 1.33)?
A.
2.26 x 10^8 m/s
B.
2.25 x 10^8 m/s
C.
2.27 x 10^8 m/s
D.
2.28 x 10^8 m/s
Show solution
Solution
The speed of light in a medium is given by v = c/n. Thus, v = (3 x 10^8 m/s) / 1.33 ≈ 2.26 x 10^8 m/s.
Correct Answer: A — 2.26 x 10^8 m/s
Learn More →
Q. If the speed of light in a vacuum is approximately 3 x 10^8 m/s, what is its value in km/s?
A.
300 km/s
B.
3000 km/s
C.
30000 km/s
D.
300000 km/s
Show solution
Solution
To convert m/s to km/s, divide by 1000. Therefore, 3 x 10^8 m/s = 300000 km/s.
Correct Answer: D — 300000 km/s
Learn More →
Q. If the speed of light in vacuum is 3 x 10^8 m/s, what is its speed in a medium with refractive index 1.5?
A.
2 x 10^8 m/s
B.
2.5 x 10^8 m/s
C.
3 x 10^8 m/s
D.
1.5 x 10^8 m/s
Show solution
Solution
The speed of light in a medium is given by v = c/n, where c is the speed of light in vacuum and n is the refractive index. Thus, v = 3 x 10^8 m/s / 1.5 = 2 x 10^8 m/s.
Correct Answer: A — 2 x 10^8 m/s
Learn More →
Q. If the speed of light in vacuum is 3 x 10^8 m/s, what is its speed in glass (n = 1.5)?
A.
2 x 10^8 m/s
B.
2.5 x 10^8 m/s
C.
3 x 10^8 m/s
D.
1.5 x 10^8 m/s
Show solution
Solution
The speed of light in a medium is given by v = c/n. Therefore, v = (3 x 10^8 m/s) / 1.5 = 2 x 10^8 m/s.
Correct Answer: A — 2 x 10^8 m/s
Learn More →
Q. If the speed of light is 3 x 10^8 m/s, what is its value in km/s? (2021)
A.
3 x 10^5 km/s
B.
3 x 10^6 km/s
C.
3 x 10^7 km/s
D.
3 x 10^8 km/s
Show solution
Solution
To convert m/s to km/s, divide by 1000. Therefore, 3 x 10^8 m/s = 3 x 10^5 km/s.
Correct Answer: A — 3 x 10^5 km/s
Learn More →
Q. If the total current in an AC circuit is 5A and the voltage is 120V, what is the impedance? (2023)
A.
24Ω
B.
20Ω
C.
30Ω
D.
15Ω
Show solution
Solution
Impedance (Z) = Voltage (V) / Current (I) = 120V / 5A = 24Ω.
Correct Answer: B — 20Ω
Learn More →
Q. If the voltage across a capacitor in an AC circuit is 100 V and the capacitive reactance is 50 ohms, what is the current? (2020)
A.
2 A
B.
0.5 A
C.
5 A
D.
10 A
Show solution
Solution
Using Ohm's law, I = V/Xc = 100 V / 50 ohms = 2 A.
Correct Answer: B — 0.5 A
Learn More →
Q. If the voltage across a capacitor in an AC circuit is 100 V and the capacitive reactance is 50 Ω, what is the current through the capacitor? (2021)
A.
2 A
B.
0.5 A
C.
5 A
D.
10 A
Show solution
Solution
Using Ohm's law, I = V/Xc = 100 V / 50 Ω = 2 A.
Correct Answer: B — 0.5 A
Learn More →
Q. If the voltage across a capacitor in an AC circuit is 100V and the capacitive reactance is 50Ω, what is the current through the capacitor? (2023)
Show solution
Solution
Current (I) = Voltage (V) / Capacitive Reactance (XC) = 100V / 50Ω = 2A.
Correct Answer: B — 2A
Learn More →
Q. If the voltage across a capacitor in an AC circuit is 100V and the capacitive reactance is 50Ω, what is the current? (2021)
A.
2A
B.
0.5A
C.
5A
D.
100A
Show solution
Solution
Using Ohm's law, I = V/Xc = 100V/50Ω = 2A.
Correct Answer: B — 0.5A
Learn More →
Q. If the voltage across a capacitor in an AC circuit is 100V and the capacitive reactance is 50 ohms, what is the current? (2023)
A.
2A
B.
0.5A
C.
5A
D.
10A
Show solution
Solution
Using Ohm's law, I = V/Xc = 100V/50Ω = 2A.
Correct Answer: A — 2A
Learn More →
Q. If the voltage across a capacitor is 100V and the capacitive reactance is 50 ohms, what is the current through the capacitor? (2022)
A.
2 A
B.
1 A
C.
0.5 A
D.
0.25 A
Show solution
Solution
I = V/Xc = 100/50 = 2 A.
Correct Answer: B — 1 A
Learn More →
Q. If the voltage across a resistor is 240V and the resistance is 60 ohms, what is the current flowing through it? (2020)
Show solution
Solution
I = V / R = 240V / 60Ω = 4A.
Correct Answer: C — 6A
Learn More →
Q. If the voltage across a resistor is halved, what happens to the current through it? (2020)
A.
It doubles
B.
It halves
C.
It remains the same
D.
It quadruples
Show solution
Solution
According to Ohm's law, if voltage is halved and resistance remains constant, the current also halves.
Correct Answer: B — It halves
Learn More →
Q. If the volume of a gas is doubled at constant temperature, what happens to its pressure?
A.
It doubles
B.
It halves
C.
It remains the same
D.
It quadruples
Show solution
Solution
According to Boyle's Law, at constant temperature, pressure is inversely proportional to volume. Therefore, if the volume is doubled, the pressure is halved.
Correct Answer: B — It halves
Learn More →
Q. If the volume of a gas is halved at constant temperature, what happens to its pressure? (2023)
A.
It doubles
B.
It halves
C.
It remains the same
D.
It quadruples
Show solution
Solution
According to Boyle's Law, if the volume is halved, the pressure doubles at constant temperature.
Correct Answer: A — It doubles
Learn More →
Q. If the volume of a gas is halved while keeping the temperature constant, what happens to the pressure of the gas?
A.
Halves
B.
Doubles
C.
Remains the same
D.
Increases by 50%
Show solution
Solution
According to Boyle's Law, if the volume is halved, the pressure doubles.
Correct Answer: B — Doubles
Learn More →
Q. If the wavelength of light used in a diffraction grating is increased, what happens to the angular separation of the fringes? (2023)
A.
Increases
B.
Decreases
C.
Remains the same
D.
Becomes zero
Show solution
Solution
The angular separation (θ) is directly proportional to the wavelength (λ). Therefore, increasing λ increases the angular separation.
Correct Answer: A — Increases
Learn More →
Q. If the wavelength of light used in a double-slit experiment is increased, what happens to the fringe separation? (2022)
A.
Increases
B.
Decreases
C.
Remains the same
D.
Becomes zero
Show solution
Solution
Fringe separation is directly proportional to the wavelength. If the wavelength increases, the fringe separation also increases.
Correct Answer: A — Increases
Learn More →
Q. If the wavelength of light used in a single-slit diffraction experiment is increased, what will happen to the position of the first minimum? (2022)
A.
It moves closer to the center
B.
It moves away from the center
C.
It remains unchanged
D.
It disappears
Show solution
Solution
The position of the first minimum in single-slit diffraction is given by a sin(θ) = λ. Increasing λ will cause θ to increase, moving the minimum away from the center.
Correct Answer: B — It moves away from the center
Learn More →
Q. If two charges +Q and -Q are placed at a distance 'd' apart, what is the electric field at the midpoint? (2020)
A.
0
B.
kQ/d^2
C.
kQ/(2d^2)
D.
kQ/d
Show solution
Solution
At the midpoint, the electric fields due to +Q and -Q cancel each other out, resulting in a net electric field of 0.
Correct Answer: A — 0
Learn More →
Q. If two identical capacitors of 4 µF each are connected in series, what is the equivalent capacitance?
A.
2 µF
B.
4 µF
C.
6 µF
D.
8 µF
Show solution
Solution
C_eq = 1 / (1/C1 + 1/C2) = 1 / (1/4 + 1/4) = 2 µF.
Correct Answer: A — 2 µF
Learn More →
Q. If two resistors of 4Ω and 6Ω are connected in series, what is the total resistance? (2023)
A.
10Ω
B.
24Ω
C.
2.4Ω
D.
12Ω
Show solution
Solution
In series, R_eq = R1 + R2 = 4Ω + 6Ω = 10Ω.
Correct Answer: A — 10Ω
Learn More →
Q. In a Carnot engine operating between 500 K and 300 K, what is the maximum efficiency of the engine? (2021)
A.
40%
B.
60%
C.
50%
D.
20%
Show solution
Solution
Efficiency (η) = 1 - (T_cold / T_hot) = 1 - (300 K / 500 K) = 0.4 or 40%.
Correct Answer: B — 60%
Learn More →
Q. In a Carnot engine operating between temperatures of 500 K and 300 K, what is the efficiency of the engine? (2023)
A.
40%
B.
50%
C.
60%
D.
70%
Show solution
Solution
Efficiency (η) = 1 - (T_cold / T_hot) = 1 - (300 K / 500 K) = 0.4 or 40%.
Correct Answer: C — 60%
Learn More →
Q. In a Carnot engine operating between two heat reservoirs at temperatures 500 K and 300 K, what is the maximum efficiency of the engine? (2023)
A.
40%
B.
60%
C.
80%
D.
20%
Show solution
Solution
Efficiency (η) = 1 - (T_cold / T_hot) = 1 - (300 K / 500 K) = 0.4 or 40%.
Correct Answer: B — 60%
Learn More →
Showing 301 to 330 of 579 (20 Pages)
