Question

Two cars moving in opposite directions approach each other with speed of 22 m/s and 16.5 m/s respectively. The driver of the first car blows a horn having a frequency 400 Hz. The frequency heard by the driver of the second car is [velocity of sound 340 m/s]:-(a) 361 Hz(b) 411 Hz(c) 448 Hz(d) 350 Hz

Answer 1

$<b>$

Option B is Correct

Answer 2

Answer:

C) 448hz

Explanation:

When both the source and observer are moving towards each other, the apparent frequency is given by - fa = fo (v+vo/v-vs)

where,

fo = original frequency of source

vs = speed of source  

vo = speed of observer

v = speed of sound  

Frequency of the horn =400Hz

Thus according to the doppler effect -

= 400(340+16.5/340-22)

= 448hz

Thus, the frequency heard by the driver of the second car is 448hz