a boy standing idle sounds a whistle to his friend at a distance of 1200 m moving away from him in a speeding car at 108 kms / hr . find the duration after which his friend is going to hear him . ( speed of sound = 330 m / sec ) .
if friend hears sound after t secs , then 330 * t = 1200 + ( 108 * 5 / 18 ) * t 300 t = 1200 t = 4 secs answer : b
add(divide(1200, 330), divide(multiply(multiply(const_3, const_10), divide(1200, 330)), 330))