Question

list three cases in which potential energy becomes kinetic energy and three cases in which kinetic energy becomes potential energy.

Answer 1

Potential energy can be converted into kinetic energy when a rock falls, a pendulum swings, or a stick of dynamite is ignited. Conversely, kinetic energy can be transformed into potential energy when a ball is thrown up, a car comes to a stop, or work is done to stretch a spring.

Step-by-step explanation:

Potential energy can be converted into kinetic energy in various cases. One example is when a rock perched on the edge of a cliff falls, its potential energy is converted into kinetic energy as it races toward the ground. Another example is a pendulum, which continuously exchanges kinetic and potential energy. Additionally, when a stick of dynamite is ignited, the chemical energy stored in it is rapidly converted into thermal energy, which is a form of kinetic energy.

Kinetic energy can also be converted into potential energy in different scenarios. For instance, when a person throws a ball up in the air, its kinetic energy gradually decreases and it gains potential energy as it climbs higher against the force of gravity. Similarly, if a car comes to a stop, its kinetic energy decreases and is transformed into potential energy stored in the car's position on a hill or slope, which is known as potential energy due to elevation.

A third case in which potential energy becomes kinetic energy is when work is transformed into kinetic energy. For example, work is done to stretch a spring, which stores potential energy. When the stretched spring is released, this potential energy is converted into kinetic energy as the spring recoils back to its original shape.

Answer 2

A) Potential energy converting into kinetic energy:
1- A ball in free fall from the top of a building: in this example, gravitational potential energy converts into kinetic energy
2- A compressed mass-spring which is released: the spring stretches and the mass is pushed away. In this example, elastic potential energy converts into kinetic energy
3- A positive test charge moving in the direction of the electric field generated by another positive charge: the charge moves from a point at higher potential to a point of lower potential, and electric potential energy converts into kinetic energy

B) Kinetic energy converting into potential energy:
1- A ball thrown vertically from the ground: the ball slows down, and the kinetic energy is converted into gravitational potential energy
2- A block sliding across a table that hits a spring, compressing it: the block slows down and its kinetic energy is converted into elastic potential energy of the spring
3- A positive test charge is fired towards another positive charge that produced an electric field: the charge moves from a point at lower potential to a point of higher potential, so it slows down and its kinetic energy is converted into electrical potential energy