Compare conductors and insulators, series and parallel circuits, switches, fuses and circuit symbols. Review suitability for your learners before teaching.
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Worksheet StudioPractice pack · Ages 7-9
Conductors, insulators & circuits
Take your time. Show your thinking.
1. In a simple SERIES circuit with two bulbs in a single loop, if one bulb’s filament breaks (blows), what happens to the other bulb: it goes out too because the single circuit loop is broken, or it stays lit?
Cell (+) ── Switch ── (−) · Closed Series Loop
2. What component has a resistance that changes significantly with temperature (used in digital thermometers and thermostats): a thermistor or a loudspeaker?
Cell (+) ── Switch ── (−) · Closed Series Loop
3. Materials such as plastic, rubber, glass and dry wood that do NOT allow electric current to flow through them are called: electrical insulators or electrical conductors?
Cell (+) ── Switch ── (−) · Closed Series Loop
4. Why are the lights and sockets in a home wired in PARALLEL rather than in series: each light is on its own branch so it receives full voltage and can be switched on or off independently without turning off the others, or parallel uses no wire?
Cell (+) ── Switch ── (−) · Closed Series Loop
5. Materials such as copper, aluminium, silver and steel that allow electric current to flow through them easily are called: electrical conductors or electrical insulators?
Cell (+) ── Switch ── (−) · Closed Series Loop
6. Why should you NEVER touch mains electrical switches, plugs or sockets with wet hands: tap water contains dissolved salts (ions) that conduct electricity and can cause a dangerous electric shock, or water freezes the switch?
Cell (+) ── Switch ── (−) · Closed Series Loop
7. What component has a resistance that decreases when brighter light shines on it (used in automatic street lights): a light-dependent resistor (LDR) or a thermistor?
Cell (+) ── Switch ── (−) · Closed Series Loop
8. If you add a second cell in series (pointing in the same direction, + to −) to a circuit with a single bulb, what happens to the bulb: it shines more brightly because the voltage pushing the current has doubled, or it goes out?
Cell (+) ── Switch ── (−) · Closed Series Loop
9. What safety device inside a plug or fusebox contains a thin wire designed to melt and break the circuit if the current becomes dangerously high: a fuse or a motor?
Cell (+) ── Switch ── (−) · Closed Series Loop
10. Why are electrical wires made with a copper metal core on the inside and a flexible plastic coating on the outside: copper conducts the electricity while the plastic insulator prevents electric shocks and short circuits, or plastic conducts electricity?
Cell (+) ── Switch ── (−) · Closed Series Loop
11. Which circuit instrument is connected IN SERIES in a loop to measure the electric current in amperes (A): an ammeter or a voltmeter?
Cell (+) ── Switch ── (−) · Closed Series Loop
12. In a standard circuit diagram, what does a long thin vertical line paired with a shorter, thicker vertical line represent: a single electrical cell, or an open switch?
Cell (+) ── Switch ── (−) · Closed Series Loop
12 questions · Seed 57 · Age guidance, not curriculum certification
View the answer key
Worksheet StudioAnswer key · Ages 7-9
Conductors, insulators & circuits
Answers and reasoning. Review before teaching.
1. In a simple SERIES circuit with two bulbs in a single loop, if one bulb’s filament breaks (blows), what happens to the other bulb: it goes out too because the single circuit loop is broken, or it stays lit?
It goes out too because the single circuit loop is broken
A break anywhere in a series loop stops current throughout the entire loop.
2. What component has a resistance that changes significantly with temperature (used in digital thermometers and thermostats): a thermistor or a loudspeaker?
Thermistor
A thermistor is a temperature-sensitive resistor.
3. Materials such as plastic, rubber, glass and dry wood that do NOT allow electric current to flow through them are called: electrical insulators or electrical conductors?
Electrical insulators
Insulators have tightly bound electrons and block the flow of electric current.
4. Why are the lights and sockets in a home wired in PARALLEL rather than in series: each light is on its own branch so it receives full voltage and can be switched on or off independently without turning off the others, or parallel uses no wire?
Each light is on its own branch so it receives full voltage and can be switched on or off independently without turning off the others
In a parallel circuit, if one lamp fails or is switched off, current still flows through the other branches.
5. Materials such as copper, aluminium, silver and steel that allow electric current to flow through them easily are called: electrical conductors or electrical insulators?
Electrical conductors
Metals have free-moving (delocalised) electrons that conduct electric current readily.
6. Why should you NEVER touch mains electrical switches, plugs or sockets with wet hands: tap water contains dissolved salts (ions) that conduct electricity and can cause a dangerous electric shock, or water freezes the switch?
Tap water contains dissolved salts (ions) that conduct electricity and can cause a dangerous electric shock
Impure water is an electrical conductor and lowers the electrical resistance of skin.
7. What component has a resistance that decreases when brighter light shines on it (used in automatic street lights): a light-dependent resistor (LDR) or a thermistor?
Light-dependent resistor (LDR)
In bright light an LDR’s resistance falls; in darkness its resistance rises.
8. If you add a second cell in series (pointing in the same direction, + to −) to a circuit with a single bulb, what happens to the bulb: it shines more brightly because the voltage pushing the current has doubled, or it goes out?
It shines more brightly because the voltage pushing the current has doubled
Two 1.5 V cells connected correctly in series supply 3.0 V, increasing the current through the bulb.
9. What safety device inside a plug or fusebox contains a thin wire designed to melt and break the circuit if the current becomes dangerously high: a fuse or a motor?
Fuse
If a fault causes excessive current, the fuse wire melts, cutting off the electricity to prevent overheating and fire.
10. Why are electrical wires made with a copper metal core on the inside and a flexible plastic coating on the outside: copper conducts the electricity while the plastic insulator prevents electric shocks and short circuits, or plastic conducts electricity?
Copper conducts the electricity while the plastic insulator prevents electric shocks and short circuits
The metal core carries current; the outer plastic sheath keeps users safe.
11. Which circuit instrument is connected IN SERIES in a loop to measure the electric current in amperes (A): an ammeter or a voltmeter?
Ammeter
An ammeter has very low resistance and is placed in series so all the current flows through it.
12. In a standard circuit diagram, what does a long thin vertical line paired with a shorter, thicker vertical line represent: a single electrical cell, or an open switch?
Single electrical cell
The long line marks the positive (+) terminal and the short thick line marks the negative (−) terminal of a cell.
12 questions · Seed 57 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 7-9
Conductors, insulators & circuits
Take your time. Show your thinking.
1. In a simple SERIES circuit with two bulbs in a single loop, if one bulb’s filament breaks (blows), what happens to the other bulb: it goes out too because the single circuit loop is broken, or it stays lit?
Cell (+) ── Switch ── (−) · Closed Series Loop
2. What component has a resistance that changes significantly with temperature (used in digital thermometers and thermostats): a thermistor or a loudspeaker?
Cell (+) ── Switch ── (−) · Closed Series Loop
3. Materials such as plastic, rubber, glass and dry wood that do NOT allow electric current to flow through them are called: electrical insulators or electrical conductors?
Cell (+) ── Switch ── (−) · Closed Series Loop
4. Why are the lights and sockets in a home wired in PARALLEL rather than in series: each light is on its own branch so it receives full voltage and can be switched on or off independently without turning off the others, or parallel uses no wire?
Cell (+) ── Switch ── (−) · Closed Series Loop
5. Materials such as copper, aluminium, silver and steel that allow electric current to flow through them easily are called: electrical conductors or electrical insulators?
Cell (+) ── Switch ── (−) · Closed Series Loop
6. Why should you NEVER touch mains electrical switches, plugs or sockets with wet hands: tap water contains dissolved salts (ions) that conduct electricity and can cause a dangerous electric shock, or water freezes the switch?
Cell (+) ── Switch ── (−) · Closed Series Loop
7. What component has a resistance that decreases when brighter light shines on it (used in automatic street lights): a light-dependent resistor (LDR) or a thermistor?
Cell (+) ── Switch ── (−) · Closed Series Loop
8. If you add a second cell in series (pointing in the same direction, + to −) to a circuit with a single bulb, what happens to the bulb: it shines more brightly because the voltage pushing the current has doubled, or it goes out?
Cell (+) ── Switch ── (−) · Closed Series Loop
9. What safety device inside a plug or fusebox contains a thin wire designed to melt and break the circuit if the current becomes dangerously high: a fuse or a motor?
Cell (+) ── Switch ── (−) · Closed Series Loop
10. Why are electrical wires made with a copper metal core on the inside and a flexible plastic coating on the outside: copper conducts the electricity while the plastic insulator prevents electric shocks and short circuits, or plastic conducts electricity?
Cell (+) ── Switch ── (−) · Closed Series Loop
11. Which circuit instrument is connected IN SERIES in a loop to measure the electric current in amperes (A): an ammeter or a voltmeter?
Cell (+) ── Switch ── (−) · Closed Series Loop
12. In a standard circuit diagram, what does a long thin vertical line paired with a shorter, thicker vertical line represent: a single electrical cell, or an open switch?
Cell (+) ── Switch ── (−) · Closed Series Loop
12 questions · Seed 57 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 7-9
Conductors, insulators & circuits
Answers and reasoning. Review before teaching.
1. In a simple SERIES circuit with two bulbs in a single loop, if one bulb’s filament breaks (blows), what happens to the other bulb: it goes out too because the single circuit loop is broken, or it stays lit?
It goes out too because the single circuit loop is broken
A break anywhere in a series loop stops current throughout the entire loop.
2. What component has a resistance that changes significantly with temperature (used in digital thermometers and thermostats): a thermistor or a loudspeaker?
Thermistor
A thermistor is a temperature-sensitive resistor.
3. Materials such as plastic, rubber, glass and dry wood that do NOT allow electric current to flow through them are called: electrical insulators or electrical conductors?
Electrical insulators
Insulators have tightly bound electrons and block the flow of electric current.
4. Why are the lights and sockets in a home wired in PARALLEL rather than in series: each light is on its own branch so it receives full voltage and can be switched on or off independently without turning off the others, or parallel uses no wire?
Each light is on its own branch so it receives full voltage and can be switched on or off independently without turning off the others
In a parallel circuit, if one lamp fails or is switched off, current still flows through the other branches.
5. Materials such as copper, aluminium, silver and steel that allow electric current to flow through them easily are called: electrical conductors or electrical insulators?
Electrical conductors
Metals have free-moving (delocalised) electrons that conduct electric current readily.
6. Why should you NEVER touch mains electrical switches, plugs or sockets with wet hands: tap water contains dissolved salts (ions) that conduct electricity and can cause a dangerous electric shock, or water freezes the switch?
Tap water contains dissolved salts (ions) that conduct electricity and can cause a dangerous electric shock
Impure water is an electrical conductor and lowers the electrical resistance of skin.
7. What component has a resistance that decreases when brighter light shines on it (used in automatic street lights): a light-dependent resistor (LDR) or a thermistor?
Light-dependent resistor (LDR)
In bright light an LDR’s resistance falls; in darkness its resistance rises.
8. If you add a second cell in series (pointing in the same direction, + to −) to a circuit with a single bulb, what happens to the bulb: it shines more brightly because the voltage pushing the current has doubled, or it goes out?
It shines more brightly because the voltage pushing the current has doubled
Two 1.5 V cells connected correctly in series supply 3.0 V, increasing the current through the bulb.
9. What safety device inside a plug or fusebox contains a thin wire designed to melt and break the circuit if the current becomes dangerously high: a fuse or a motor?
Fuse
If a fault causes excessive current, the fuse wire melts, cutting off the electricity to prevent overheating and fire.
10. Why are electrical wires made with a copper metal core on the inside and a flexible plastic coating on the outside: copper conducts the electricity while the plastic insulator prevents electric shocks and short circuits, or plastic conducts electricity?
Copper conducts the electricity while the plastic insulator prevents electric shocks and short circuits
The metal core carries current; the outer plastic sheath keeps users safe.
11. Which circuit instrument is connected IN SERIES in a loop to measure the electric current in amperes (A): an ammeter or a voltmeter?
Ammeter
An ammeter has very low resistance and is placed in series so all the current flows through it.
12. In a standard circuit diagram, what does a long thin vertical line paired with a shorter, thicker vertical line represent: a single electrical cell, or an open switch?
Single electrical cell
The long line marks the positive (+) terminal and the short thick line marks the negative (−) terminal of a cell.
12 questions · Seed 57 · Age guidance, not curriculum certification