Selected MCQ

Current Question
Which condition leads to total internal reflection?
  • A. Light moving from lower to higher refractive index
  • B. Incident angle less than critical angle
  • C. Light moving from higher to lower refractive index with angle exceeding critical angle
  • D. Any angle in vacuum
Correct Answer: C
Explanation:
Total internal reflection occurs beyond the critical angle in denser to rarer medium.
Related Question 1
Which symmetry leads to conservation of energy (Noether’s theorem)?
  • A. Spatial symmetry
  • B. Time translation symmetry
  • C. Rotational symmetry
  • D. Gauge symmetry
Correct Answer: B
Explanation:
Invariance under time translation implies energy conservation.
Related Question 2
In a relativistic particle collision, total energy is conserved but:
  • A. Mass is always conserved separately
  • B. Mass can convert into energy
  • C. Momentum is not conserved
  • D. Charge is not conserved
Correct Answer: B
Explanation:
Relativity allows interconversion of mass and energy via (E=mc^2).
Related Question 3
Which system has highest internal energy?
  • A. Solid
  • B. Liquid
  • C. Gas
  • D. Vacuum
Correct Answer: C
Explanation:
Gas particles have highest kinetic energy.
Related Question 4
The Doppler effect for light leads to redshift when:
  • A. Source approaches observer
  • B. Source moves away
  • C. Observer moves toward source
  • D. Wavelength decreases
Correct Answer: B
Explanation:
Receding source increases wavelength (redshift).
Related Question 5
Which phenomenon leads to quantization of atomic energy levels?
  • A. Classical mechanics
  • B. Boundary conditions on wavefunctions
  • C. Thermal motion
  • D. Friction
Correct Answer: B
Explanation:
Allowed solutions of Schrödinger equation are discrete due to constraints.