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General
Easy
Question
An Indian submarine and an enemy submarine move towards each other during maneuvers in motionless water in the Indian ocean. The Indian submarine moves at 50 km/h, and the enemy submarine at 70 km/h. The Indian sub sends out a sonar signal (sound wave in water) at 1000 Hz. Sonar waves travel at 5500 km/h. What is the frequency detected by the Indian submarine
- 1.02 kHz
- 2 kHz
- 2.5 kHz
- 4.7 kHz
The correct answer is: 1.02 kHz
Frequency detected by Indian submarine
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