A 'light clock' moving sideways ticks slower for a stationary observer because:

  1. the clock is heavier
  2. the light has to travel a longer diagonal path at the same speed c
  3. the mirrors get closer
  4. light slows down
Answer

B) the light has to travel a longer diagonal path at the same speed c

Derivation of time dilation. SLO P-11-F-03 · Understanding

Physics MCQ · More Special Relativity MCQs · Practise