A 1.0kg ball is thrown into the air with an initial velocity of 30m/s. How much potential energy does the ball have when it reached the top of its ascent?

Answer: 450J

Explanation:

Mass of ball = 1.0kg

kinetic energy = ?

velocity of the ball = 30m/s

Kinetic energy is the energy possessed by a moving object. It is measured in joules, and depends on the mass (m) of the object and the velocity (v) by which it moves

i. e K. E = 1/2mv²

KE = 1/2 x 1.0kg x (30m/s) ^2

KE = 0.5 x 1.0 x 900

KE = 450J

(Recall that kinetic energy is equal to potential energy at the top of its ascent)

So, if KE = 450J; PE = 450J

Thus, the potential energy of the ball is 450 joules.