Question

A source of sound of frequency 450 cycle /sec is moving towards a stationary observer with 34 m /s speed. if the speed of sound is 340 m/s then the apparent frequency will be

Answer 1

f = s2-s1/f2-f1
The frequency will be(f2) = 340-34/450-f1
f2= 306/450-f1
f2+f1=306×450
2f=306×450
2f = 137700
f=137700/2
f = 68850
This gives the apparent frequency

Answer 2

Answer:

The apparent frequency will be 500 cycle/s

Explanation:

Given that,

Frequency of sound = 450 cycle/s

Speed of wave  = 34 m/s

Sped of sound = 340 m/s

The apparent frequency will be

Formula of apparent frequency is defined as,

$n' =n(\dfrac{v}{v-v_{0}})$

Where, n = frequency of sound

v = speed of sound

$v_{0}$ =speed of source

Put the value in to the formula

$n'=450\times(\dfrac{340}{340-34})$

$n'=500\ cycle/s$

Hence, The apparent frequency will be 500 cycle/s