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Questions
State three conditions for the formation of an echo.
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Solution
- The minimum distance between the source of sound and its reflector should be 17 m.
- Reflected sound should reach the person atleast 0.1 second after the original sound is heard.
- The size of the reflecting surface must be much larger than the wavelength of the sound wave to ensure strong reflection.
- The original sound must be loud enough so that the reflected wave still has enough energy to be clearly heard by the ear.
Notes
Students should refer to the answer according to their questions.
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