Answer to Question #78917 in Physics for Nandu

Question

If the time interval between Lightening and thunder in 2sec. What is the distance of the point of lightening (speed of the sound in air is 346m/hr).

Answer 1

Since the speed of light is much faster than the speed of sound we can neglect the time that light from the lightning travels to the observer. Thus the distance to the lightning is 2 sec∙346 m/sec=692 m.