A body of mass 5 kg is moving with velocity of `v=(2hati+6hatj)ms^(-1)` at t=0s. After time t=2s, velocity of body is `(10 hati+6 hatj)`, then change in momentum to body is

Options

A. `40 hat(i)" kgms"^(-1)`
B. `20 hat(i)" kgms"^(-1)`
C. `30 hat(i)" kgms"^(-1)`
D. `(50 hat(i)+30 hat(j))" kgms"^(-1)`

Answer

A

Explanation

Mass, `m=5` kg
Change in velocity, `v_(f)-v_(i)=[(10-2) hat(i)+(6-6)hat(j)]`
Change in momentum `=m Delta v=5 [8hat(i)]=40 hat(i)" kgms"^(-1)`