Question

The position-time graph of a particle of mass 40 g is shown here Which of the following statement is true about the graph?

• A. The particle receives an impulse of $8\times {10}^{-4}kgm{s}^{-1}$ after every 1 s
• B. The particle receives an impulse of $8\times {10}^{-4}kgm{s}^{-1}$after every 2 s
• C. The particle receives an impulse of $4\times {10}^{-4}kgm{s}^{-1}$ after every 1 s
• D. The particle receives an impulse of $4\times {10}^{-4}kgm{s}^{-1}$ after every 2 s

Answer 1

Answer: (B)

The particle receives an impulse of $8\times {10}^{-4}kgm{s}^{-1}$after every 2 s

Given m = 4 $\times$ ${10}^{-2}$ kg

Velocity just before 2 seconds = 1 $\times$ ${10}^{-2}$ m/sec

Velocity just after 2 seconds = -1 $\times$ ${10}^{-2}$ m/ sec

Therefore, change in velocity = 2 $\times$ ${10}^{-2}$ m/ sec

Impulse = mass * change in velocity

= 4 $\times$ ${10}^{-2}$ kg $\times$ 2 $\times$ ${10}^{-2}$ m/ sec

= 8 $\times$ ${10}^{-4}$ kgm/s