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A 120 g mass has a velocity vecv=2hati+5...

A 120 g mass has a velocity `vecv=2hati+5hatj m s^(-1)` at a certain instant. Its kinetic energy is

A

`5 J`

B

`2 J`

C

`3 J`

D

`8 J`

Text Solution

Verified by Experts

The correct Answer is:
`(3)`
`K.E = 1/2 M(vec v. vec v)`
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NARAYNA-WORK , ENERGY & POWER -EXERCISE - 1 (C.W)
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