# Using energy

Mind Map by , created over 6 years ago

## GCSE Physics P1 (Using energy) Mind Map on Using energy, created by sanakaka2 on 05/06/2013.

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 Created by sanakaka2 over 6 years ago
Electrical Energy 2
moving and storing heat
GCSE Maths Symbols, Equations & Formulae
Sociology Key Words
Physics P1
Electromagnetic Waves
Electrical energy
Heat Transfer
Using energy
1 Different forms of energy
1.1 Chemical energy = energy stored in fuel (including food), and is released when chemical reactions take place
1.1.1 Kinetic energy is the energy of a moving object
1.1.1.1 Gravitational potential energy (or GPE) is the energy of an object due to its position
1.1.1.1.1 Electrical energy is energy transferred by an electric current
1.1.1.1.1.1 Thermal (heat) energy is the energy of an object due to its temperature, partly because of the random kinetic energy of the particles of the object
1.1.1.1.1.1.1 Elastic (or strain) energy is the energy stored in a springy object when we squash or stretch it
1.1.1.1.1.1.1.1 Sound energy is energy created from sounds
1.1.2 Energy can only be transformed from one form to another
1.1.2.1 Energy cannot be lost it can ONLY be changed from 1 form to another
1.1.2.1.1 EXAMPLE= torch chemical energy in battery => electrical energy => light energy + thermal energy
2 Energy conservation
2.1 CONSERVATION OF ENERGY ! -- energy cannot be created or destroyed
3 Useful energy, Wasted energy ,Efficiency
3.1 Useful energy is energy transferred to where we want it to go
3.1.1 Wasted energy is energy which is not usefully transferred
3.1.1.1 Wasted energy spreads out to its surroundings.
3.1.1.1.1 EXAMPLE = the gears of a car get hot when the car is running, so thermal energy transfers from the gear box to the surrounding air
3.1.2 Useful energy eventually transfers to its surroundings too
3.1.2.1 EXAMPLE= , the useful energy supplied to the road wheels of a car changes into thermal energy of the tyres, the road and the surrounding air
3.2 Energy becomes less useful when its spread out
3.3 The Sankey diagram to the left shows how we can represent useful and wasted energy outputs from a machine or appliance
3.3.1 We can sum this up by using this general equation: energy supplied = useful energy delivered + energy wasted
3.3.1.1 For any device that transfers energy, we can use this to work out the energy efficiency of it:
3.3.1.1.1 useful energy transferred by __________________________________ device total energy supplied to device
3.3.1.1.1.1 Efficiency =