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A wave of frequency 100 Hz s sent along ...

A wave of frequency 100 Hz s sent along a string towards a fixed unit. When this wave travels back after reflection a node is formed at a distance of 10 cm from the fixed end of the string.The speeds of incident (or reflected) waves are :

A

`10 m//s`

B

`5 m//s`

C

`40 m//s`

D

`20 m//s`

Text Solution

Verified by Experts

The correct Answer is:
D
Frequency v= 100 Hz
`(lambda)/(2)=10 cm`
`:.` Wave length `lambda=20 cm 20xx10^(-2)m`
`:.` Speed of the wave `v= v lambda`
`=100xx20xx10^(-2)`
`=20 m//s`
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