Physics
Grade-8
Easy
Question
A child was observing a thunderstorm from the glass window of his room. He hears thunder after seeing the lightning, even if these two events occur at the same time. This is because the speed of light ____ the speed of sound.
- >
- <
- =
- Any of the above
Hint:
The light travels faster than the sound in the air. So the light caused by the thunder could be visible a bit earlier than the sound is heard.
The correct answer is: >
- The light travels faster than the sound.
- Even when the thunder causes light and sound at the same time, the light will be visible before the sound is heard.
- Sound is a mechanical wave that travels in a solid medium faster than air.
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