

From, 1/2 mv2 + 1/2 I ω2 = mgh
1/2mv2 + 1/2 (1/2 mr2) ω2 = mgh
3/4 mv2 = mgh
h = 3v2/4g = 3 × 52/4 × 9.8 = 1.913 m
If s is the distance up the inclined plane, then as
sin θ = h/s
s = h/sin θ = 1.913/sin 30° = 3.826 m
Time taken to return to the bottom
