A body of mass 2 kg hits a wall at an angle of $30^{\circ}$ with the normal and returns at the same

Question

A body of mass 2 kg hits a wall at an angle of $30^{\circ}$ with the normal and returns at the same angle with the same speed of $10 \mathrm{~m/s}$. The impact time was 0.1 s. The force exerted on the wall is

Professor PC Thomas Classes · Answer

Change in momentum along normal = $2mv \cos(30^{\circ}) = 2 	imes 2 	imes 10 	imes \frac{\sqrt{3}}{2} = 20\sqrt{3}$. Force = Change in momentum / time = $\frac{20\sqrt{3}}{0.1} = 200\sqrt{3}$ N.