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A bullet of mass 20g fired from a rifle ...

A bullet of mass 20g fired from a rifle is found to cover the distance of 30m in 4 s. Assuming that the speed of the bullet to be constant, find its kinetic energy.

A

`0.5625J`

B

`56.25J`

C

`30.08J`

D

`1.125J`

Text Solution

Verified by Experts

The correct Answer is:
B
Uniform speed of bullet `v=(30m)/(4s)`
`=7.5ms^(-1)`
Kinetic energy,
`E_(k)=(1)/(2)mv^(2)`
`=(1)/(2)xx(0.02kg)(7.5ms^(-1))^(2)`
`=0.5625J`
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KUMAR PRAKASHAN-WORK AND ENERGY -QUESTION & ANSWER (CHOOSE THE CORRECT OPTION FROM THOSE GIVEN BELOW EACH QUESTION)
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