Final answer:
The gravitational potential energy of a 0.5 kg ball at a height of 15 m is 73.5 joules. When the ball reaches the ground, its gravitational potential energy is 0 joules.
Step-by-step explanation:
The question pertains to the calculation of gravitational potential energy (U) of a ball with a mass m = 0.5 kg falling from a certain height h. The gravitational potential energy at any height is given by the equation U = mgh, where g is the acceleration due to gravity, which is approximately 9.8 m/s2 on the surface of the Earth.
Here, it appears there might be a slight confusion in the question where 'initial speed = 10 m/s2' is mentioned, which is likely a typo and should be disregarded as not relevant to the calculation of potential energy.
Using the formula for gravitational potential energy:
- At the highest point (h = 15 m): U = mgh = 0.5 kg * 9.8 m/s2 * 15 m = 73.5 J
- On the ground: U = mgh = 0.5 kg * 9.8 m/s2 * 0 m = 0 J
Therefore, at the highest point, the ball has 73.5 joules of gravitational potential energy, and on the ground, its gravitational potential energy is zero.