Potential energy is the stored energy in an object due to its position, condition, or configuration. It’s energy that has the potential to do work in the future but isn’t actively being used at the moment.
Types of Potential Energy:
Gravitational Potential Energy: Energy stored in an object due to its height above the ground. For example, a book held up in the air has gravitational potential energy because of its position relative to the Earth.
Elastic Potential Energy: Energy stored in stretched or compressed objects, like a stretched rubber band or a compressed spring.
Chemical Potential Energy: Energy stored in chemical bonds, such as in batteries or food. When the bonds break, the energy is released and can be used for work.
Formula for Gravitational Potential Energy:
PE=m×g×h
where:
m = mass of the object
g = gravitational acceleration (on Earth, about 9.8 m/s²)
h = height above the ground
Potential energy is important because it can convert to other forms, like kinetic energy (energy of motion), allowing objects to move, heat up, or power various processes.
1. A rock with a mass of 5 kg is lifted to a height of 10 meters. Calculate the gravitational potential energy of the rock.
2. A 2 kg object is moved from a height of 4 meters to 8 meters above the ground. How much does its gravitational potential energy increase?
3. A book with a mass of 1.5 kg has a gravitational potential energy of 29.4 J. At what height above the ground is it positioned?
4. A stretched rubber band holds potential energy. Describe what happens to this potential energy when you release the rubber band.
5. Explain how the chemical potential energy stored in food provides energy for our bodies. What happens to this energy once we consume and digest the food?