Question

A truck starts from rest and rolls down a hill with constant acceleration. It travels a distance of 400m in 20s. Calculate the acceleration of the truck and force acting on it, if its mass is 7 metric ton.

Answer 1

Dear Student,

$$\begin{gathered} \mathrm{s}=400\mathrm{m} \\ \mathrm{t}=20\mathrm{s} \\ \mathrm{u}=0 \\ \mathrm{m}=7\mathrm{metric}\mathrm{tonnes}=7\times 1000\mathrm{kg}=7000\mathrm{kg} \\ \mathrm{s}=\mathrm{ut}+\frac{1}{2}{\mathrm{at}}^2 \\ 400=0\times 20+0.5\times \mathrm{a}\times {\left(20\right)}^2 \\ 200\mathrm{a}=400 \\ \mathrm{a}=2\mathrm{m}/{\mathrm{s}}^2 \\ \mathrm{F}=\mathrm{ma} \\ \mathrm{F}=7000\times 2 \\ \mathrm{F}=14000\mathrm{N} \end{gathered}$$