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The position vector of a particle is giv...

The position vector of a particle is given by `vec r = (2t hati+5t^(2)hatj)m` (t is time in sec). Then the angle between initial velocity and initial acceleration is

A

zero

B

`45^(@)`

C

`90^(@)`

D

`180^(@)`

Text Solution

Verified by Experts

The correct Answer is:
C
The position ………… `(vecV)= (dvecr)/(dt) = 2hati+10t hatj`
`veca = 10 hatj`
`vecV(t = 0) = 2hati`
`veca(t=0)=10hatj`
`implies vecV _|_veca(theta = 90^(@))`
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