Question

A car is moving with velocity u on a road running parallel to a row buildings. The distance b/w
row of a buildings and road is d. The driver sounds the horn. He recives the echo offer a time t is
(v is velocity of sound waves)

Answer 1

Question:-A car is moving with velocity u on a road running parallel to a row buildings. The distance b/wrow of a buildings and road is d. The driver sounds the horn. He recives the echo offer a time t is(v is velocity of sound waves)

Solution:-

distance travelled by car in time t=ut

distance covered by sound in time t=d+(d-ut)=2d-ut

velocity=distance travelled/time taken

=(2d-ut)/t

so,the velocity of the echo will be (2d-ut)/t

so,the velocity of the echo will be (2d-ut)/t{hope it helps you}