Final answer:
The subject of this question is Physics, and the grade level is High School. The question discusses the energy transformation involved when a child slides down a playground slide, converting potential energy into kinetic energy.
Step-by-step explanation:
The subject of this question is Physics and the grade level is High School.
The question describes a scenario of a child sliding down a playground slide, which is a classic example of a situation involving potential energy and kinetic energy. At the top of the slide, the child has potential energy due to their height above the ground. As they slide down, this potential energy is converted into kinetic energy, which is the energy of motion. The speed at which the child slides down the slide depends on factors such as the height of the slide and the presence of friction.