Question 23

Gravitational potential energy is converted into kinetic energy.

When a boulder rolls downhill, its gravitational potential energy, which is stored due to its height, is converted into kinetic energy as it gains speed.

A) Gravitational potential energy is converted into kinetic energy.

This option accurately describes the energy conversion taking place when the boulder rolls downhill. As the boulder descends, the height decreases, resulting in a loss of gravitational potential energy, which is transformed into kinetic energy, causing the boulder to accelerate.

B) Chemical potential energy is converted into gravitational potential energy.

This option is incorrect because there is no chemical potential energy involved in the scenario of a boulder rolling downhill. Chemical potential energy pertains to the energy stored in the bonds of chemical compounds and is not relevant to the gravitational and kinetic energy conversion occurring in this context.

C) Kinetic energy is converted into gravitational potential energy.

This option is also incorrect. When the boulder rolls downhill, it is actually losing gravitational potential energy, not converting kinetic energy into gravitational potential energy. As the boulder moves down, it speeds up, which indicates that kinetic energy is increasing, not the other way around.

D) Elastic potential energy is converted into thermal energy.

This option is incorrect as well. Elastic potential energy applies to objects that can be stretched or compressed, such as springs, and is not applicable to a boulder rolling downhill. There is no elastic potential energy in this scenario that would convert into thermal energy.

Conclusion

The correct answer is clearly A, as it correctly identifies the energy transformation that occurs when a boulder rolls downhill. Options B, C, and D fail to accurately describe the process at hand, highlighting the significance of understanding gravitational potential and kinetic energy in the context of motion.