Selected MCQ

Current Question
Which quantity is vector?
  • A. Mass
  • B. Speed
  • C. Velocity
  • D. Energy
Correct Answer: C
Explanation:
Velocity has magnitude and direction.
Related Question 1
Which thermodynamic quantity remains constant in adiabatic process?
  • A. Temperature
  • B. Pressure
  • C. Entropy (reversible case)
  • D. Volume
Correct Answer: C
Explanation:
Reversible adiabatic process is isentropic.
Related Question 2
Which quantity is invariant in all reference frames?
  • A. Velocity
  • B. Time
  • C. Rest mass
  • D. Length
Correct Answer: C
Explanation:
Rest mass is Lorentz invariant.
Related Question 3
Which quantity is scalar?
  • A. Velocity
  • B. Force
  • C. Acceleration
  • D. Energy
Correct Answer: D
Explanation:
Energy has magnitude only.
Related Question 4
Which quantity remains invariant under Lorentz transformations?
  • A. Velocity
  • B. Time
  • C. Spacetime interval
  • D. Length
Correct Answer: C
Explanation:
The spacetime interval is invariant in all inertial frames.
Related Question 5
If the net external torque on a system is zero, which quantity is conserved?
  • A. Linear momentum only
  • B. Angular momentum
  • C. Kinetic energy only
  • D. Power
Correct Answer: B
Explanation:
Zero external torque implies conservation of total angular momentum.