Question

A block of mass 2 kg placed on a long frictionless horizontal table is pulled horizontally by a constant force F. It is found to move 10 m in the first seconds. Find the magnitude of F.

Answer 1

Given:
Mass of the block, m = 2 kg,
Distance covered, S = 10 m and initial velocity, u = 0
Let a be the acceleration of the block.
Using, $\mathrm{S}=ut+\frac{1}{2}a{t}^2$, we get:
$$\begin{gathered} 10=\frac{1}{2}a\left(2^2\right) \\ \Rightarrow 10=2a \\ \Rightarrow a=5\mathrm{m}/{\mathrm{s}}^2 \end{gathered}$$
∴ Force, F = ma = 2 × 5 = 10 N