A physics teacher uses a ramp making an angle of 20.° with the horizontal to show the students the rolling motion of different objects. First, she releases from rest a disk of diameter d from a height of 50. cm above the floor. Then, she releases a uniform spherical ball of diameter d from a height of h. The two objects reach the end of the ramp at the same speed. Find h. Consider that the two objects roll to the bottom without slipping.