Q: Vibrating mobile phone on wooden table sounds louder than held in hand. Why?
Ans: Vibrating mobile phone on wooden table sounds louder than held in hand because surface area of wooden table is greater than surface area of phone.
Explanation:
Loudness of sound is directly proportional to the surface area of the vibrating body. when mobile phone is in contact with the table, the vibration of the mobile phone is transmitted to the surface of the table whose surface area is very large as compared to the surface area of phone and hence sound becomes louder.
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