Stored and moving energy, particles and floating
Stored and moving energy, particles in solids, liquids and gases, and what floats or sinks. Read one part at a time and tap “I know this”. Then test yourself in the quiz.
Know it already? Jump straight to the quiz
Stored or moving
| Stored (potential) energy | Moving (kinetic) energy |
|---|---|
| A stretched elastic band | A moving car |
| The battery in a torch that is off | A ball that rolls |
| Food in your lunchbox | A cheetah that runs |
Hold a basketball and a tennis ball at the same height: the heavier basketball has more stored energy. Drop the tennis ball on top of the basketball and the tennis ball bounces very high!
Particles
A gas takes the shape of its container. Blow air into a balloon: more air pushes on the rubber and the balloon gets bigger. Inside a soap bubble is air.
Floating and sinking
- A piece of wood floats; a coin sinks.
- A big steel ship floats, but a steel nail sinks: the ship’s hollow shape holds lots of air.
- Ice floats on water: ice is lighter than the same amount of water.
A snow igloo in a hot place? It melts into a liquid.
Remember this and test yourself
- Potential (stored) energy is waiting to be used: a stretched elastic band, a battery, food.
- Kinetic energy is the energy of movement: a moving car, a running cheetah.
- A ball rolling downhill: stored energy becomes movement energy.
- In a gas the particles are far apart and move fast; that is why you smell a braai from far away.
- Wood floats, a coin sinks; a steel ship floats because its hollow shape holds lots of air.
Write these points in your book. Read them again the night before the test.
Potential = Parked (energy waits). Kinetic = Kicking (energy moves).
Important words
First say what the word means, then turn the card over.
Match column A to column B
Tap a word in column A, then its meaning in column B. You can also start in column B.
True or false?
Read the question and the answer. Is the answer right? Tap True or False.
Now the real quiz!
The quiz has many more questions on this topic. Every question shows straight away whether you are right and explains why.
Take the quiz: Stored and moving energy, particles and floating- Read one part together and ask your child to tell it back in their own words.
- The ticks (“I know this”) are saved on this device only. We never ask for names or emails.
Follows CAPS for Grade 4 Natural Sciences and Technology. Always check your teacher’s notes and textbook too.