Question

The energy that something has because of its position--a book held 20 feet above the ground has more of this than a book held 5 feet off the ground.

Answer 1

Potential energy is the energy an object possesses due to its position, such as a book held above ground level. It increases with the object's height and can be calculated using the formula PE = mgh. Examples like lifting a box or a car parked on a high level illustrate this concept.

Step-by-step explanation:

The energy something has because of its position is known as potential energy. For instance, a book held 20 feet above the ground has more potential energy than the same book held 5 feet off the ground due to its position. This is because potential energy is related to the object's height above the reference point, generally considered as ground level. The potential energy (PE) can be calculated using the formula PE = mgh, where m is the mass of the object, g is the acceleration due to gravity, and h is the height above the reference point.

To illustrate with an example, lifting a 20 kg box through a vertical distance results in an increase in potential energy, calculated by the weight of the box multiplied by the height it is raised, which comes out to approximately 400 joules (J) of energy for a 2-meter lift. Similarly, a car parked at the top of a parking garage has potential energy due to its elevated position, irrespective of how it got there.

Answer 2

The most common types of energy an object can have are:

- Kinetic energy: energy related to the movement. If an object has velocity, it has kinetic energy. The faster the object, higher is its kinetic energy.

- Potential energy: energy related to the height, to gravity. The higher (bigger height) an object is from a reference point, higher is its potential energy.

So the energy of a book held 20 feet above ground being higher than the energy of a book held 5 feet above ground, this energy is the potential energy.

Therefore the correct option is the third one.