Question

Two children are at opposite ends of an aluminium rod. One strikes the end of the rod with a stone. Find the ratio of the time taken by the sound wave air and in aluminium to reach the second child. [v of al =6420m/s, v of air =346m/s]

Answer 1

Answer

Velocity of sound in air= 346 m/s
Velocity of sound wwave in aluminium= 6420 m/s
Let length of rode be 1

Time taken for sound wave in air, t1= 1 / Velocity in air
Time taken for sound wave in Aluminium, t2= 1 / Velocity in aluminium

Therefore, t1 / t2 = Velocity in aluminium / Velocity in air = 6420 / 346 = 18.55 : 1

Hope it helps..........