$1.$ The image shows a $50$ cm high ramp on which an object can slide. The object starts from rest to slide down the ramp.

a$.$ Determine the mechanical energy when the object is $50$ cm high when at rest.

b$.$ Using Conservation of Mechanical Energy, find the velocity of the object when it is at the $30$ cm position.

$E=KE+U$

$KE=\frac{1}{2}m{v}^2$

$U=mgh$

$\frac{1}{2}m{v}^2-\frac{1}{2}m{x}_0^2+mgh-mg{h}_0=0$