A 4 m long metal bar tapped by a hammer on one end. A microphone recording the sound at the other end picks up two sound pulses; one which traveled through the metal bar and other which was traveling through room temperature air. These two pulses are separated by 11 msec. What is the speed of sound in the metal

Explanation:

Speed of sound in air at room temperature = 346 m /s

Let speed of sound in metal given = v m /s

Time take by sound wave travelling through air = 4 / 346 = .01156 s

Time taken by sound wave travelling through metal = 4 / v s

Given ,

.01156 - 4 / v = 11 x 10⁻³ s = .011 s ( time taken by sound travelling in air is more )

4 /v = .01156 - .011 = .00056

v = 4 / .00056 = 7142.85 m /s

trig 15.3 cos