Question

In the figure given the position-time graph of a particle of mass $0.1\, kg$ is shown. The impulse at $t=2\, s$ is :

• A. $0.2\, kg\, m\, s ^{-1}$
• B. $-0.2\, kg\, m\, s ^{-1}$
• C. $0.1\, kg\, m\, s ^{-1}$
• D. $-0.4\, kg\, m\, s ^{-1}$

Answer 1

Answer: (B)

The impulse is given by
$I =$ change in momentum
$=\Delta=m \Delta v$
$=m \frac{\Delta x}{\Delta t}$
Given $m=0.1\, kg , \frac{\Delta x}{\Delta t}=\frac{4.0}{2} ms ^{-1}$
$\therefore I=0.1 \frac{4}{2}=-0.2\, kg - ms ^{-1}$