Year 4 Science: Insulators in everyday life
Part of the Year 4 Science switches, conductors and insulators chapter. Chapter overview · whole chapter on one page
Insulators in everyday life
Insulators do not let electricity flow through them. Plastic, rubber, wood, glass and dry paper are common insulators.
Electrical wires have a plastic or rubber coating. The metal inside carries the electricity, and the insulating coating keeps the electricity inside the wire, so it does not reach our hands.
The table shows the results of the conductor tester for the four insulators, and the glass and the other materials.
| Material between the clips | Kind of material | Lamp lights? (conductor or insulator) |
|---|---|---|
| copper coin | metal | lights: conductor |
| steel paper clip | metal | lights: conductor |
| aluminium foil | metal | lights: conductor |
| pencil lead (graphite) | not a metal | lights: conductor |
| plastic ruler | not a metal | stays off: insulator |
| rubber band | not a metal | stays off: insulator |
| wooden stick | not a metal | stays off: insulator |
| glass | not a metal | stays off: insulator |
Key ideas
- An insulator does not let electricity flow through it.
- Plastic, rubber, wood and glass are insulators.
- Wires have an insulating coating to keep the electricity inside the wire.
- The metal inside a wire is a conductor.
Method. Find the plastic ruler row.
- Read the row. The plastic ruler does not light the lamp.does not light
- Name the kind. So the plastic ruler is an insulator.insulator
- Write the answer. insulator
Check. Plastic is an insulator. ✓
Method. Count the insulator rows.
- Read the table. The insulators are plastic ruler, rubber band, wooden stick and glass.four
- Count them. There are four insulators in the table.4
- Write the answer. 4
Check. Four insulators and four conductors make eight materials. ✓
Method. Think about the coating.
- Think about the coating. The coating stops the electricity from leaving the wire.stops
- Name the kind of material. Materials that stop electricity from flowing are insulators.insulator
- Write the answer. insulator
Check. A plastic or rubber coating is an insulator. ✓
Watch out
Watch out: glass is an insulator, so a glass cup does not carry electricity. But a glass object does not protect you from mains electricity, so never test it with mains.
Try it at home or school (with a grown-up). Look at the cable of a lamp at home with a grown-up. Find the plastic coating and the metal inside, if you can see them. Do not cut or touch any cable that is plugged in.
Exam tip
Grown-up tip. Ask: “What is the outside of the wire made of? Why does it need that covering?” Let your child explain that the coating is an insulator.
Exercise 10D Insulators in everyday life
Method. Read the table.
- Read the plastic row. The plastic ruler does not light the lamp.does not light
- Write the answer. insulator
Check. Plastic does not conduct. ✓
Method. Read the table in section 10.4.
- Read the rubber row. The rubber band does not light the lamp.does not light
- Decide. So a rubber band is not a conductor.no
- Write the answer. no
Check. Rubber is an insulator. ✓
Method. Read the table in section 10.4.
- Read the wood row. The wooden stick does not light the lamp.does not light
- Write the answer. insulator
Check. Wood is an insulator. ✓
Method. Count the insulator rows.
- Count them. Plastic ruler, rubber band, wooden stick and glass are the insulators.four
- Write the answer. 4
Check. Four insulators in the table. ✓
Method. Read the table in section 10.4.
- Read the glass row. The glass does not light the lamp.does not light
- Write the answer. no
Check. Glass is an insulator. ✓
Method. Read the key idea in section 10.4.
- Read the key idea. Wires have a plastic or rubber coating that is an insulator.plastic
- Write the answer. plastic
Check. Rubber is also a common coating. ✓
Method. Read the insulator rows.
- Read the rows. The insulator rows are plastic ruler, rubber band, wooden stick and glass.insulator rows
- Write the answer. Accept any one of: plastic ruler, rubber band, wooden stick, glass.
Check. Any one of these does not let electricity flow. ✓
Method. Think about an insulator in the tester.
- Think about the loop. An insulator keeps the loop broken.broken
- Decide. So the lamp stays off, and the answer is no.no
- Write the answer. no
Check. Insulators keep the lamp off. ✓
Method. Count the materials that are not metals.
- Count the rows. Pencil lead, plastic ruler, rubber band, wooden stick and glass are not metals.five
- Write the number. So five materials are not metals.5
- Write the answer. 5
Check. Three metals and five other materials make eight. ✓
Method. Read the table in section 10.4.
- Read the wood row. The wooden stick does not light the lamp.does not light
- Decide. So the wooden stick is an insulator, and Ruby is not right.no
- Write the answer. no
Check. Where a material comes from does not decide whether it conducts. ✓
Method. Think about a fair test.
- Think about the test. The sponge goes between the clips, like the other materials.between the clips
- Write one thing. Use the same cell, bulb and clips as the other tests.same cell
- Write the answer. Accept any safe plan, such as: use the same cell, bulb and clips, and put the dry sponge between the clips.
Check. Keep the other parts of the tester the same. ✓
Method. Think about the coating.
- Think about the coating. The coating is an insulator.insulator
- Write the reason. It stops the electricity from leaving the wire, which keeps people safe.keeps people safe
- Write the answer. Accept any sentence that says the insulator stops the electricity from leaving the wire, so it keeps people safe.
Check. The coating protects the people near the wire. ✓