Answer:
19.8m/s
Step-by-step explanation:
Given parameters:
Mass of the ball = 10kg
Height of the rail = 20m
Unknown:
Velocity at the bottom of the rail = ?
Solution:
The velocity at the bottom of the rail is its final velocity.
Using the appropriate motion equation, we can find this parameter;
V² = U² + 2gH
V is the final velocity
U is the initial velocity
g is the acceleration due to gravity
H is the height
the ball was rolled from rest, U = 0
V² = O² + 2 x 9.8 x 20
V = 19.8m/s