A thin spherical shell, of mass $m=20kg$ and radius $R,$ rolls smoothly from rest down a

ramp at an angle $=30.$ Assume that the spherical shell has the centre of mass inertia

$I_{\text{c}\text{o}\text{m}}=\frac{2}{3}m{R}^2.$ Draw a free body diagram and answer the following questions:

$($a$)$ If the ball descends a vertical hight $h=10m$ to reach the bottom of the ramp, what is its

speed at the bottom of the ramp?

$($b$)$ What are the magnitude and direction of frictional force that acts on the ball as it rolls

down the ramp?