A train is passing by a platform at a constant speed of 40 m/s. The train horn is sounded at a frequency of 378 Hz. Find the overall change in frequency as detected by a person standing on the platform, as the train moves from approaching to receding. (Take velocity of sound in air as 320 m/s)

A train is passing by a platform at a constant speed of 40 m/s. The train horn is sounded at a frequency of 378 Hz. Find the overall change in frequency as detected by a person standing on the platform, as the train moves from approaching to receding. (Take velocity of sound in air as 320 m/s)

A
104 Hz
B
92 Hz
C
84 Hz
D
96 Hz

Solution:

For situation l, $f_{ap 1} = \frac{v - 0}{v - v_{s}} \times f$

= $\frac{320}{320 - 40} \times 378 = 432 Hz$

For situation 2, $f_{{ap}_{2}} = \frac{v}{v - (- v_{S})} \times f = 336 Hz$

$f = f_{ap 1} - f_{ap 2} = 96 Hz$

Related content

Top Courses After 12th Science with PCM, PCB and PCMB

Subject Change Application in School and College

CBSE Class 10 Result 2024: Is the Release Date Early? Check Expected Schedule

Mizoram NEET Merit List 2023

Government Jobs After 12th Arts Stream

Chhattisgarh NEET UG Merit List 2023

Technical Courses After 12th – Eligibility, Duration, Salary, Top Colleges

Sikkim NEET UG Merit List 2023

How to Start Preparing for NEET From Class 10?

UP NEET UG Merit List 2023