A train is traveling at 30.0 m/s relative to the ground in still air. The frequency of the note emitted by the train whistle is 262 Hz. The speed of sound in air should be taken as 344 m/s. Part A What frequency fapproach is heard by a passenger on a train moving at a speed of 18.0 m/s relative to the ground in a direction opposite to the first train and approaching it

Question

Lilah Solomon

Physics

14 May, 11:59

A train is traveling at 30.0 m/s relative to the ground in still air. The frequency of the note emitted by the train whistle is 262 Hz. The speed of sound in air should be taken as 344 m/s. Part A What frequency fapproach is heard by a passenger on a train moving at a speed of 18.0 m/s relative to the ground in a direction opposite to the first train and approaching it

+3

Answers (1)

Know the Answer?

Antoine Mckenzie · Answer 1

vs=speed of source=30 m/s

vl=speed of listener=18 m/s

actual frequency = f = 262 Hz

v = speed of sound = 344 m/s

apparent frequency = f' = ?

a) f' = (v+vl / v - vs) f

= (344+18 / 344-30) x 262

= (362/314) x262

= 302 Hz

b) f' = (v-vl / v+vs) f

= (344-18 / 344+30) x 262

= (326/374) x262

= 228.3 Hz

= 302 Hz