Same chapter3 marksDifficulty: Medium
Distinguish between a musical sound and a noise.
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3 marksDifficulty: Medium
What is an echo, and state two of its practical uses.
Original Khojo Papers practice question — not from a past board paper.
Answer
An echo is the sound heard again after being reflected from a distant surface. Echo sounding is used to measure the depth of the sea and to locate shoals of fish, and the same principle in SONAR is used to detect submarines and in ultrasound scanning to image the inside of the body.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Bats and dolphins navigate by the same method.
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