Topics · Primary Science · Energy: Forms & Conversion
Forms of energy and how they convert
Energy comes in several forms and changes from one to another. It is never made and never destroyed — and a question asking what happened almost always wants a chain of conversions written out in order.
- 150 exam papers analysed
- appears in 99% of P6 Science papers
- ~2 min read
01 The forms that get named
Use the proper names. “Energy” alone, or an everyday word, rarely scores.
| Form | Where you meet it |
|---|---|
| Kinetic | anything moving |
| Potential (gravitational) | anything raised up |
| Elastic potential | a stretched or squashed spring |
| Light | a lamp, the sun |
| Heat | a fire, a warm object |
| Sound | anything making a noise |
| Electrical | a current in a circuit |
| Chemical | food, fuel, a battery |
02 Energy converts; it is not used up
Energy changes form. It is never created and never destroyed, which is why “the energy was used up” is wrong however sensible it sounds.
When something seems to lose energy, it has gone somewhere — usually as heat and sound, spread out and hard to use again.
So a question asking where the energy went wants what form it became, not that it disappeared.
03 Writing a conversion chain
The standard question describes something happening and asks for the energy changes. Write them as a chain with arrows.
- Start with the store. Food and fuel and batteries hold chemical energy; a raised object holds potential.
- Follow it through each step, naming a form each time. Do not skip stages.
- Include heat and sound where they occur, even if they are not the useful output. Markers look for them.
- A child on a swing: potential → kinetic → potential, with a little heat and sound lost each swing, which is why it slows.
- A car: chemical (fuel) → kinetic + heat + sound.
- A person cycling: chemical (food) → kinetic + heat.
04 Sources, and why the sun matters
The sun is the source of almost all energy on Earth. Plants capture its light and store it as chemical energy in food; animals eat plants; fuels are the remains of living things from long ago.
Renewable sources do not run out — sun, wind, water, tides. Non-renewable ones do — coal, oil, gas.
That connects to the environment topic: the reason for saving energy is that non-renewable sources are limited and burning them causes harm.
05 How to say them
These are words most children have never said out loud, and a word you cannot say is a word you avoid using. Capitals mark the syllable you lean on. Tap the speaker to hear it.
- energysayEN-uh-jee
What is needed to make things happen. It changes form but is never made or destroyed.
- kinetic energysayki-NET-ik
The energy of anything moving.
- potential energysaypuh-TEN-shuhl
Stored energy, in something raised up or stretched.
- chemical energysayKEM-i-kuhl
Energy stored in food, fuel and batteries.
- convertsaykuhn-VURT
To change from one form of energy to another.
- renewablesayri-NYOO-uh-buhl
A source that does not run out: sun, wind, water, tides.
06 What each level is tested on
The same topic, asked differently as it goes up. The percentage is the share of papers at that level in which it appears.
- P6
The forms of energy, writing conversion chains, sources of energy, and links to the environment. Marked in nearly every P6 paper.
Practise P6 Energy: Forms & Conversion — 10 questions →99% of P6 papers
07 Mistakes worth knowing about
Each of these is wrong. Decide why before you open it.
“The energy was used up.”
It changed form, usually to heat and sound. Say what it became.
“The battery makes energy.”
It stores chemical energy and converts it to electrical. Nothing makes energy.
“Chemical → kinetic” for a car.
Incomplete. Heat and sound are produced too, and markers look for them.
“Food gives you energy, which is a form of its own.”
The form is chemical energy. Use the proper name.
“The swing stops because it runs out of energy.”
The energy became heat and sound through friction and air resistance. It left the swing; it did not cease to exist.
Now try it
10 questions across 1 levels, marked as you go with the working shown.