Question
A Boy plants a bomb at a place in Diwali and starts
running at 30 m/s. After 54 seconds the bomb was blast. In how much time the sound of blast will be listen by the boy, if the speed of sound is 300 m/s.Solution
Speed of Boy = 30 m/s Speed of sound of Bomb = 640 m/s Distance travelled by a Boy in 54 seconds = (30 × 54) m The time taken by the sound of blast to be listen by him T = D/S = (30 ×54)/(Relative Speed ) = `[(30xx54)/(300-30)]` = `(30xx54)/270` = 6 seconds
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