A body is moving with uniform speed v on a horizontal circle from A as shown in the figure. Change in velocity in the first quarter revolution is

Options

A. North
B. `sqrt(2)`v South-West
C. `sqrt(2)` v North-west
D. 2v West

Answer

B

Explanation

For quarter revolution `Deltavecv=vecv_(2)-vecv_(1)` and angle between `vecv_(1)` and `vecv_(2)` is `90^(@)`

`Deltav=sqrt(v_(1)^(2)+v_(2)^(2)-2v_(1)v_(2)cos theta)`
`Deltav=sqrt(v_(2)^(2)+v_(1)^(2))=sqrt(v^(2)+v^(2))=sqrt(2v)," "alpha =tan^(-1)v/v,=45^(@):." "Deltavecv=sqrt(2)v` (South west)