P1.2 - Useful energy Flashcards
Name the 8 different types of energy
Light Sound Kinetic (movement) Nuclear Electrical Gravitational Potential Elastic Potential Chemical
What happens when an object falls to the ground?
- It gains speed.
- Its gravitational potential energy decreases.
- Its kinetic energy increases.
What can energy do?
It can be transferred from one form to another.
What is conservation of energy?
- Energy cannot be created or destroyed.
- Energy can be transferred from one form to another, or from one place to another.
In terms of energy, what happens when you burn a fuel?
Chemical energy is transferred to the surroundings, which get hotter.
What is a machine?
Something that transfers energy from one place to another or from one form to another.
What is useful energy?
Energy which is transferred to the place we want and in the form we want it.
What is wasted energy?
Energy which is not usefully transferred.
What happens when energy spreads out?
It gets more and more difficult to use for further energy transfers.
What is the formula for input energy?
Input energy (energy supplied)
=
Useful energy transferred
\+
Energy wastedWhat is the efficiency of an appliance formula?
The efficiency of an appliance = useful energy transferred by the appliance ÷ total energy supplied to the appliance (x100%)
What is the highest efficiency of a machine?
100%
What measures can be taken to make a machine more efficient?
- Friction
- Air resistance
- Electrical resistance
- Noise due to vibrations
How can energy transfer be represented?
In a Sankey Diagram
