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The position vector of a particle is giv...

The position vector of a particle is given by `vecr=vecr_(0)` (1-at)t, where t is the time and a as well as `vecr_(0)` are constant. After what time the particle retursn to the starting point?

A

a

B

`(1)/(a)`

C

`a^(2)`

D

`(1)/(a^(2))`

Text Solution

Verified by Experts

The correct Answer is:
B
Returning at starting point means `vecr=vec0`
`rArr r_(0)(1-at)t=0`
`rArr (1-at)t=0`
`rArr t=0, t=(1)/(a)`
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