The correct option is B −0.2 kg m sec−1
From the x−t graph, velocity of particle is given by:
v=slope of x-t curve=dxdt
⇒From t=0 to t=2 s, slope of x−t curve is constant, so velocity is,
∴v=slope of x-t curve=4−02−0=2 m/s
Just after t=2 s, x=constant v=dxdt=0 m/s
⇒At t=2 s, particle is undergoing a transition in velocity from vi=2 m/s to vf=0
From impulse momentum-theorem on particle:
J=ΔP=mvf−mvi ...(i)
∴J=0.1(0−2)=−0.2 kg m sec−1