Physics
Grade-8
Easy
Question
Pick the wrong statement about echo.
- Reflected sound is called echo.
- Roaring of thunder is an example of echo.
- Echo is produced when sound is incident on hard and polished surface.
- Echoes are resulted from a fixed number of reflecting surfaces.
Hint:
Multiple echoes can be heard when a sound is reflected from various reflecting surfaces.
The correct answer is: Echoes are resulted from a fixed number of reflecting surfaces.
- The reflected sound is called an echo.
- Roaring of thunder is an example of echo.
- Echo is heard when sound is incident on a hard and polished surface.
- Multiple echoes may be heard one after the other when sound gets repeatedly reflected from various reflecting surfaces.
- Therefore, statement given in option d is wrong.
- So, the correct option is d.
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