Question

Imagine a 1 km long railway tunnel. At one end P of this tunnel, is a CD player playing songs. At the other end Q, are two sensitive recorders R1 and R2 which can record sound of even very low volume.

R1 receives the sound through the air in the tunnel and R2 through the steel rail. Both recorders are on all the time.

A song begins playing at P beginning at 10.00 and ends at 10.03. If we compare the recordings R1 and R2, we would find that 

1. R1 will play the song slower
2. R2 will play the song slower
3. the start of recording in R1 will be later than in R2
4 .the start of recording in R2 will be later than in R1​

Answer 1

Answer:

Explanation:

We will observe that R1 will play the song slower because it is receiving sound signals through air whereas R2 is receiving sound signals through rail track and we know that sound travels faster in dense medium(Soilds).