In the figure given below, the position-time graph of a particle of mass `0.1kg` is shown. The impuslse at `t=2` sec is

Options

A. `0.2kgmsec^-1`
B. `-0.2kgmsec^-1`
C. `0.1kgmsec^-1`
D. `-0.4kgmsec^-1`

Answer

B

Explanation

Velocity between `t=0` and `t=2` sec
`impliesv_i=(dx)/(dt)=(4)/(2)=2(m)/(s)`
velocity at `t=2` sec,`v_f=0`
Impulse`=`change in momentum`=m(v_f-v_i)`
`=0.1(0-2)=-0.2kgmsec^-1`