Circuits: conductors and insulators
How to test whether a material is a conductor or an insulator, and why it matters. 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
The conductor test
| Bulb lights? (conductor) | Bulb stays off? (insulator) |
|---|---|
| Steel paper clip | Plastic ruler |
| Copper wire | Rubber |
| Aluminium foil | Glass |
| Pencil lead (graphite) | Wood, paper |
Tap water conducts only a tiny bit: in this test the bulb does not light. But the much stronger electricity from the plug points in your home can pass through water and through you, so keep water away from plugs and switches. Graphite (pencil lead) is a non-metal that does conduct.
If a learner tests six materials and three light the bulb, three are conductors and three are insulators.
Why insulators matter
- Wire is covered in plastic to protect the person from the current.
- Tool handles have rubber: rubber does not conduct.
- Electricians wear rubber gloves. Power lines hang from glass or ceramic insulators, so the current cannot run down the pole.
- Two batteries in series: the bulb burns brighter.
Short circuit and overloading
A short circuit is when current takes an easy shortcut path. A fuse cuts off too much current. Too many appliances in one socket: the wiring can overheat and catch fire. The main switch cuts all power in an emergency.
Remember this and test yourself
- A complete circuit has a source (battery), a path (wires) and a device (bulb).
- A conductor lets current through; an insulator stops it.
- Metals conduct best; copper is good and affordable. Plastic, rubber and glass are insulators.
- Test: put the material in the gap of a circuit; if the bulb lights, it is a conductor.
- Tap water conducts: keep water away from electricity.
Write these points in your book. Read them again the night before the test.
Metal = mates with the current (conductor). Plastic, rubber, glass = the current’s wall (insulator).
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: Circuits: conductors and insulators- 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 6 Natural Sciences and Technology. Always check your teacher’s notes and textbook too.