A particle is moving on a circular path with constant speed v then the change in its velocity after it has desceibed an angle of `60^(@)` will be

Options

A. `vsqrt(2)`
B. `(v)/(2)`
C. `vsqrt(3)`
D. v

Answer

D

Explanation

(d) `v_(1)=vhatj`
`v_(2)=-vsin thetahtj+vcosthetahatj`
`Deltav=v_(2)-v_(1)`
`=-vsinhati+v(cstheta-1)hatj`
`|Deltav|=2Vsin(theta)/(2)`
`=2vsin(60^(@))/(2)=2vsin30^(@)`
`=2vxx(1)/(2)=v`