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A spring stores 5J of energy when stretc...

A spring stores 5J of energy when stretched by 25 cm. It is kept vertical with the lower end fixed. A block fastened to its end is made to undergo small oscillations. If the block makes 5 oscillations each second what is the mass of the block?

A

`0.16kg`

B

`1.6kg`

C

`16kg`

D

`0.016kg`

Text Solution

Verified by Experts

The correct Answer is:
C
`x=25xm=0.24m, E=5J, f=5`
`So, T=1/5sec`
Now , PE=`1/2kx^2`
`rarr` `1/2kx^2=5`
`= 1/2k(0.25)^2=5`
`=k=160N/m`
Again `T=2pi(sqrt(m/k))`
`rarr` `1/2=2pi(sqrt(m/160))`
`implies m=0.16kg`
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