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Velocity of a particle at some instant i...

Velocity of a particle at some instant is `v=(3hat i + 4hat j + 5hat k) m//s`. Find speed of the particle at this instant.

A

12

B

7

C

-12

D

`5sqrt2`

Text Solution

Verified by Experts

The correct Answer is:
D
Magnitude of velocity vector at any instant of time is the speed of particle. Hence,
`Speed= v or |v| = sqrt(3^2 + 4^2 + 5^2 ) = 5sqrt2 m//s`
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