Question

A particle of mass 2 kg is initially at rest. A force acts on it whose magnitude changes with time. The force time graph is shown below. The velocity of the particle after 10 s is –

• A. 20 m/s
• B. 10 m/s
• C. 75 m/s
• D. 50 m/s

Answer 1

Answer: (D)

50 m/s

Answer 2

Q Area bounded by the curve = DP

\ $\left( \frac{1}{2} \times 2 \times 10 \right)$ + (2 × 10) + $\left( \frac{1}{2} \times 30 \times 2 \right)$+ $\left( \frac{1}{2} \times 4 \times 20 \right)$

= 2(v₂ – 0)

Ž v₂ = 50 m/s