| ⇦ | 
| ⇨ |
A train moving at a speed of 220 ms⁻¹ towards a stationary object, emits a sound of frequency 1000 Hz. Some of the sound reaching the object gets reflected back to the train as echo. The frequency of the echo as detected by the driver of the train is: (speed of sound in air is 330 ms⁻¹)
Options
(a) 3500 Hz
(b) 4000 Hz
(c) 5000 Hz
(d) 3000 Hz
Correct Answer:
5000 Hz
Explanation:
Frequency of the echo detected by the driver of the train is (According to Doppler effect in sound)
f’ = (v + u / v – u) f
where, f = original frequency of source of sound
f’ = Apparent frequency of source beacause of othe relative motion between source and observer.
f’ = (330 + 220 / 330 – 220) 1000 = 5000 Hz.
Related Questions: - In a double slit experiment, the two slits are 1mm apart and the screen is placed 1 m
- Two bodies of mass 0.25 kg each moving towards each other with velocity
- Sand is being dropped on a conveyor belt at the rate of M kg/s. The force necessary
- Surface tension of water will be minimum at
- A copper disc of radius 0.1 m is rotated about its centre, with 10 revolutions
Topics: Waves
(80)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- In a double slit experiment, the two slits are 1mm apart and the screen is placed 1 m
- Two bodies of mass 0.25 kg each moving towards each other with velocity
- Sand is being dropped on a conveyor belt at the rate of M kg/s. The force necessary
- Surface tension of water will be minimum at
- A copper disc of radius 0.1 m is rotated about its centre, with 10 revolutions
Topics: Waves (80)
Subject: Physics (2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
18000+ students are using NEETLab to improve their score. What about you?
Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.
Share this page with your friends
Leave a Reply