Physics-
General
Easy
Question
An Indian submarine is moving in “Arab Sagar” with a constant velocity. To detect enemy it sends out sonar waves which travel with velocity 1050 m/s in water. Initially the waves are getting reflected from a fixed island and the reflected waves are coming back to submarine. The frequency of reflected waves are detected by the submarine and found to be 10% greater than the sent waves.
Now an enemy ship comes in front, due to which the frequency of reflected waves detected by submarine becomes 21% greater than the sent waves. The speed of Indian submarine is
- 10 m/sec
- 50 m/sec
- 100 m/sec
- 20 m/sec
The correct answer is: 50 m/sec
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