Question

Two children use a homemade "telephone" consisting of two paper cups attached by an aluminum wire which is 8.4 m long. Determine the time for the "sound" to travel from one cup to the other. How does this compare with the time for sound to travel the same distance through air? (speed of sound in aluminum is 5100 m/s, in air is 343 m/s)

Answer 1

Step-by-step explanation:

Distance over wire of aluminium d = 8.4 m

velocity of sound in aluminium = 5100 m /s

time required = distance / velocity

= 8.4 / 5100 s

= .001647 s

velocity of sound in air = 343 m /s

time required = distance / velocity

= 8.4 / 343 s

= .024489 s

Difference of time

= .024489 - .001647

= .022842 s

= 22.842 ms .