Answer:
its speed when its height was half that of its starting point is 25.46 m/s
Explanation:
Given;
final speed of the roller coaster, v = 36 m/s
Applying general equation of motion;
V² = U² + 2gh
where;
V is the final speed of the roller coaster
U is the initial speed of the roller coaster = 0
h is the height attained at a given velocity
36² = 0 + (2 x 9.8)h
1296 = 19.6 h
h = 1296/19.6
h = 66.1224 m
when its height was half that of its starting point, h₂ = ¹/₂ h
h₂ = ¹/₂(66.1224 m) = 33.061 m
At h = 33.061 m, V = ?
V² = U² + 2gh
V² = 0 + 2 x 9.8 x 33.061
V² = 648
V = √648
V = 25.46 m/s
Therefore, its speed when its height was half that of its starting point is 25.46 m/s