Question

a basketball dropped onto the court begins bouncing. what happens to the balls gravitational potential energy when the ball hits the ground? a) all of it transforms to kinetic energy. b) the ground absorbs all of the energy. c) the ball uses all of its energy to bounce. d) some of it transforms to thermal energy.

Explanation:

• Gravitational potential energy (\(U = mgh\), where \(m\) is mass, \(g\) is acceleration due to gravity, and \(h\) is height) depends on the height of the ball. When the ball hits the ground (\(h = 0\)), its gravitational potential energy is converted.
• In a real - world scenario (not a perfectly elastic collision), energy is not conserved in a purely kinetic - potential sense. There are non - conservative forces (like air resistance and internal friction within the ball and ground interaction).
• According to the law of conservation of energy, the total energy of an isolated system is conserved. When the ball hits the ground, some of the gravitational potential energy (which was converted to kinetic energy as it fell) is transformed into thermal energy (due to friction and deformation, causing heating) along with other forms like sound energy.
• Option A is incorrect because in a non - ideal situation (real - world bounce), not all energy is just kinetic (there are energy losses). Option B is wrong as the ground doesn't absorb all the energy in the sense of 'destroying' it; energy is just transformed. Option C is incorrect because the ball doesn't use all its energy to bounce (there are energy dissipations).

Answer:

D. Some of it transforms to thermal energy.