Examples of Energy Conversion
Physics: Edexcel IGCSE, topic 4.1.3
Examples of Energy Conversion
Energy is never created or destroyed, only converted from one store to another. Here are some examples of this process:
A moving object hitting an obstacle
- The object's energy is in the kinetic store at the start because it is moving.
- When the object collides with the obstacle, energy is converted to:
- The kinetic store of the obstacle (making it move),
- The thermal store of the object and the obstacle (the particles in the object and the obstacle vibrate more).
- Some energy remains in the object's kinetic store as it moves away after the collision.
An object projected upwards
- The object's energy is initially in the kinetic store as it moves upwards.
- The object's energy is slowly transferred from the kinetic store to the gravitational potential store as it slows down and climbs higher.
- Once the object reaches its highest point, all of its energy is in the gravitational potential store.
- As the object falls again, energy transfers from the gravitational potential store to the kinetic store.
A vehicle slowing down
- To begin with, the vehicle's energy is in the kinetic store.
- The brakes do work slowing the car down. During this process, energy is dissipated (lost) through heat and sound.
Bringing water to a boil in an electric kettle
- Energy transfers from the electrical store of the mains power supply to the thermal store of the water.
An object accelerated by a constant force
- Work is done by a force on an object.
- This work is converted to the object's kinetic store.
Test yourself on Examples of Energy Conversion
Energy Conversion in an Object Projected Upwards
When an object is projected upwards, what store is its energy in at its highest point?