Hey there! We receieved your request
Stay Tuned as we are going to contact you within 1 Hour
One of our academic counsellors will contact you within 1 working day.
Click to Chat
1800-5470-145
+91 7353221155
Use Coupon: CART20 and get 20% off on all online Study Material
Complete Your Registration (Step 2 of 2 )
Sit and relax as our customer representative will contact you within 1 business day
OTP to be sent to Change
An engine whestles at a frequency of 256Hz moves towards a wall with a velocity of 50m/s. How many number of beats will be sounded to the engine?
Doppler's fomula is
n' = n (v -vo)/(v-vs)
where n' = apprant frequency
n = original frequency
v = spped of sound in air that is 330 m/s
vo = speed of observer
vs = speed of the source
Here n = 256 hz vo = 0 vs = 50m/s pluging in the values we will get n = 497 hz
now with this frequency the sond will reflect from the wall so the source will be stationary
we will again use the same formula
n" = n (v -vo)/(v-vs)
now vo = 50m/s , vs = 0 and v =330m/s n" = frequency heard by the observer
now pluging in the values we will have
n" = 497(330 - 50)/(330 - 0)
= 497x 280/330
= 422hz so the no of beats heard by the observer is n" - n = 422 - 256= 166 beats per second
Register Yourself for a FREE Demo Class by Top IITians & Medical Experts Today !