hi i have a doubt is there a difference in hearing thunder with respect to time ,when lightning occurs with respect to 2 observer who are 3km apart or is it negligible.
2007-09-02 05:25:16 · 4 answers · asked by Sandeep N 1 in Science & Mathematics ➔ Weather
The distance between the observers does not matter. The only thing that is important is the distance of each observer from the lightning strike.
Light travels essentially instantaneously on a small scale, so it can be thought of as infinitely fast (no time delay). Sound, however, travels at about 340 meters per second in normal conditions. That means it takes 2.94 seconds for sound to travel 1 kilometer.
As a rough estimate, for every 3 seconds you count between the light and the sound of a lightning strike, it is 1 kilometer away from you. So, if the sound is heard 9 seconds after the flash is seen, it's about 3 kilometers away from the observer.
2007-09-02 05:50:22 · answer #1 · answered by lithiumdeuteride 7 · 0⤊ 0⤋
The difference must be measured in terms of relative distance from the lightning event. If both individuals are equal distance from the vent they will hear the thunder at exactly the same time unless there is a barrier to the sound wave in one or both instances.
Since the speed of sound will be identical in this case, same relative altitude and small distance then the only other block to the sound energy would be a barrier of some sort. If one person was in a soundproof room for example they would clearly not hear the thunder. Like wise if one person had a clear line of sight to the event and the other was on the back side of a large hill then the person in clear line of sight would hear the sound first. The person on the backside of the hill would hear the sound later since the sound wave would need to go over the top of the hill first. Likewise if two persons are three km apart but one if 100 meters from the event and the other is 2.9 kilometers from the event then the one nearer would clearly hear the thunder first. It is all about relative distance to the event and topography not their relative positions to each other.
2007-09-02 12:41:15 · answer #2 · answered by tk 4 · 0⤊ 0⤋
Lightning travels at 344 m/s at 21 degrees c, so it will be about 14.5 seconds for 5 km and 8.7 seconds for 3 km
2007-09-02 12:36:58 · answer #3 · answered by Mr Nodozo 2 · 0⤊ 0⤋
It would be negligible. Sound travels at slightly faster speed in humid air so if one person is in more humid air then the other person he/she would hear the thunder sooner but the time difference would be very small and imperceptible.
2007-09-02 12:34:57 · answer #4 · answered by Randy S 1 · 0⤊ 0⤋