Question

A moving body weighing 400 N possesses 500 J of kinetic energy, calculate the velocity with which the body is moving ?( g = 10 m/s2)

Answer 1

Dear Student,

$$\begin{gathered} \mathrm{We}\mathrm{know}\mathrm{that}\mathrm{force}\mathrm{will}\mathrm{accelerate}\mathrm{on}\mathrm{object}, \\ \mathrm{F}=\mathrm{mg} \\ 400=\mathrm{m}\times 10 \\ \mathrm{m}=40\mathrm{kg} \\ \mathrm{Kinetic}\mathrm{energy},\mathrm{KE}=\frac{1}{2}{\mathrm{mv}}^2 \\ 500=\frac{1}{2}\times 40\times {\mathrm{v}}^2 \\ {\mathrm{v}}^2=\frac{500\times 2}{40} \\ \mathrm{v}=\sqrt{25}=5\mathrm{m}/\mathrm{s} \end{gathered}$$