Q 11-04-043NEETJEE MainMedium
A $2$ kg body at rest is acted on by a force that rises uniformly from $0$ to $100$ N in $0.1$ s and then falls uniformly back to zero in the next $0.1$ s. The speed of the body afterwards is
Answer: (D) $5$ m/s
Concept. Impulse $=$ area under the force–time graph $= m\Delta v$.
Step 1. Area. $\dfrac12 \times 0.2 \times 100 = 10$ N s.
Step 2. Speed. $\dfrac{10}{2} = 5$ m/s.
Answer. $5$ m/s (Option D).
Solution by Sreeraj P, M.Sc Physics