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Question
A ball falls off a table and reaches the ground in 1 s. Assuming g=10 m/s2, calculate its speed on reaching the ground and the height of the table.
Solution
1) Velocity on reaching the ground
v = u + gt
v = final velocity
u = initial velocity
t = time
g = gravitational acceleration.
Doing the substitution we have :
v = 0 + 10 × 1 = 10 m/s
= 10 m/s
2) The height of the table
S = ut + 1/2gt²
Doing the substitution we have :
S = 0 × 1 + 1/2 × 10 × 1
s = 0 + 5
= 5 meters
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