Lightning and thunder reach an observer at different times because
ASound travels much faster than light
BLight travels much faster than sound
CSound and light travel at the same speed
DSound bends but light travels straight
Answer & Solution
Correct answer: B. Light travels much faster than sound
1. Light moves at 3 x 10^8 m/s.
2. Sound moves at about 340 m/s in air.
3. Light arrives almost instantly; sound takes seconds to cover km.
4. Hence we see lightning before we hear thunder.
_Source: Selina Concise Physics Class 9, Ch 8 Sound (Mistral OCR'd PDF), section on light vs sound_
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