A ball is dropped from the top of a building. In the absence of air resistance, the ball will hit the ground with a speed of 49 m/s. The height of the building is
A) 25 m.
B) 5.0 m.
C) 240 m.
D) 120 m.
E) 10 m.

Question

Quizplus · Accepted Answer

The final velocity of the ball, v = 49 m/s
The initial velocity of the ball, u = 0 m/s (because it was dropped)
Acceleration due to gravity, g = 9.8 m/s^2

We can use the equation v^2 = u^2 + 2as, where s is the height of the building.

Substituting the values, we get:
49^2 = 0^2 + 2 x 9.8 x s
Solving for s, we get:
s = 120.02 m (rounded to two decimal places)

Therefore, the height of the building is 120 meters. Answer choice D is the correct answer.

A Ball Is Dropped from the Top of a Building