13 Jun 2026

Relativity Standard Problems

Standard competitive exam problems in relativity with answer key.

relativity gate-2024 csir-net-2023 jest-2022

These are original standard problems based on frequently tested competitive-exam patterns.

Q: The Lorentz factor is
A: $\gamma=1/\sqrt{1-v^2/c^2}$
B: $\gamma=\sqrt{1-v^2/c^2}$
C: $\gamma=1+v/c$
D: $\gamma=v/c$
ANSWER: A
SOURCE: GATE 2024 style
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Q: The invariant interval in one spatial dimension is commonly written as
A: $c^2t^2+x^2$
B: $c^2t^2-x^2$
C: $ct+x$
D: $t^2+x^2/c^2$
ANSWER: B
SOURCE: CSIR-NET 2023 style
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Q: The relativistic energy-momentum relation is
A: $E^2=p^2c^2+m^2c^4$
B: $E=pc^2$
C: $E^2=p^2c^4-m^2c^2$
D: $E=mv$
ANSWER: A
SOURCE: JEST 2022 style
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Q: Proper time is measured in the frame where the two events occur at
A: the same position
B: the same time only
C: infinite separation
D: speed greater than $c$
ANSWER: A
SOURCE: GATE 2021 style
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Q: A moving rod of proper length $L_0$ appears to have length
A: $\gamma L_0$
B: $L_0/\gamma$
C: $L_0+\gamma$
D: $0$
ANSWER: B
SOURCE: CSIR-NET 2020 style
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Q: A particle with zero rest mass must move in vacuum at speed
A: $0$
B: $c$
C: $c/2$
D: greater than $c$
ANSWER: B
SOURCE: GATE style
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Q: Relativistic momentum is
A: $mv$
B: $\gamma mv$
C: $mv/\gamma$
D: $mc^2$
ANSWER: B
SOURCE: CSIR-NET style
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Q: Events separated by a spacelike interval can be made simultaneous in
A: no inertial frame
B: some inertial frame
C: only the rest frame of light
D: every inertial frame
ANSWER: B
SOURCE: JEST style

Problem Sheet Standard MCQs