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 10-12
Conductors, insulators & circuits
Take your time. Show your thinking.
1. What circuit component allows current to flow in ONE direction only (and emits light when it is an LED): a diode (or light-emitting diode) or a fixed resistor?
Cell (+) ── Switch ── (−) · Closed Series Loop
2. 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
3. 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
4. What happens when you open (turn off) a switch in a simple series circuit: it creates a gap (open circuit) that stops the current flowing and turns the bulb off, or it makes the bulb brighter?
Cell (+) ── Switch ── (−) · Closed Series Loop
5. What happens if two identical cells in a torch are put in facing opposite directions (+ touching +): their voltages cancel out and the bulb will not light, or the bulb shines twice as bright?
Cell (+) ── Switch ── (−) · Closed Series Loop
6. Which circuit instrument is connected IN PARALLEL across a component to measure the potential difference (voltage) in volts (V): a voltmeter or an ammeter?
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. In a standard circuit diagram, what component is represented by a circle with an “X” (cross) inside it: a filament lamp (bulb) or a battery?
Cell (+) ── Switch ── (−) · Closed Series Loop
9. For an electric current to flow and light up a bulb, what kind of path must the circuit form from one terminal of the battery to the other: a complete (closed) loop with no gaps, or a broken (open) loop?
Cell (+) ── Switch ── (−) · Closed Series Loop
10. In a standard circuit diagram, what component is represented by a circle with the letter “M” inside it: an electric motor or a buzzer?
Cell (+) ── Switch ── (−) · Closed Series Loop
11. In a parallel circuit, how does the total current leaving the battery compare to the currents in the individual parallel branches: the total current equals the sum of the currents in the branches, or the total current is zero?
Cell (+) ── Switch ── (−) · Closed Series Loop
12. 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
12 questions · Seed 104743 · Age guidance, not curriculum certification
View the answer key
Worksheet StudioAnswer key · Ages 10-12
Conductors, insulators & circuits
Answers and reasoning. Review before teaching.
1. What circuit component allows current to flow in ONE direction only (and emits light when it is an LED): a diode (or light-emitting diode) or a fixed resistor?
Diode (or light-emitting diode)
A diode has low resistance in the forward direction and very high resistance in reverse.
2. 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.
3. 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.
4. What happens when you open (turn off) a switch in a simple series circuit: it creates a gap (open circuit) that stops the current flowing and turns the bulb off, or it makes the bulb brighter?
It creates a gap (open circuit) that stops the current flowing and turns the bulb off
A switch controls a circuit by safely opening or closing the conducting gap.
5. What happens if two identical cells in a torch are put in facing opposite directions (+ touching +): their voltages cancel out and the bulb will not light, or the bulb shines twice as bright?
Their voltages cancel out and the bulb will not light
Cells in series must be aligned positive-to-negative so their voltages add together.
6. Which circuit instrument is connected IN PARALLEL across a component to measure the potential difference (voltage) in volts (V): a voltmeter or an ammeter?
Voltmeter
A voltmeter has very high resistance and is connected across (in parallel with) a component.
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. In a standard circuit diagram, what component is represented by a circle with an “X” (cross) inside it: a filament lamp (bulb) or a battery?
Filament lamp (bulb)
A circle containing a cross is the standard circuit symbol for an indicator or lighting lamp.
9. For an electric current to flow and light up a bulb, what kind of path must the circuit form from one terminal of the battery to the other: a complete (closed) loop with no gaps, or a broken (open) loop?
A complete (closed) loop with no gaps
Current only flows around a continuous, closed conducting pathway.
10. In a standard circuit diagram, what component is represented by a circle with the letter “M” inside it: an electric motor or a buzzer?
Electric motor
A circle with an “M” represents an electric motor that converts electrical energy into kinetic rotation.
11. In a parallel circuit, how does the total current leaving the battery compare to the currents in the individual parallel branches: the total current equals the sum of the currents in the branches, or the total current is zero?
The total current equals the sum of the currents in the branches
By Kirchhoff’s current law (conservation of charge), current splits at a junction and recombines on return.
12. 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.
12 questions · Seed 104743 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 10-12
Conductors, insulators & circuits
Take your time. Show your thinking.
1. What circuit component allows current to flow in ONE direction only (and emits light when it is an LED): a diode (or light-emitting diode) or a fixed resistor?
Cell (+) ── Switch ── (−) · Closed Series Loop
2. 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
3. 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
4. What happens when you open (turn off) a switch in a simple series circuit: it creates a gap (open circuit) that stops the current flowing and turns the bulb off, or it makes the bulb brighter?
Cell (+) ── Switch ── (−) · Closed Series Loop
5. What happens if two identical cells in a torch are put in facing opposite directions (+ touching +): their voltages cancel out and the bulb will not light, or the bulb shines twice as bright?
Cell (+) ── Switch ── (−) · Closed Series Loop
6. Which circuit instrument is connected IN PARALLEL across a component to measure the potential difference (voltage) in volts (V): a voltmeter or an ammeter?
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. In a standard circuit diagram, what component is represented by a circle with an “X” (cross) inside it: a filament lamp (bulb) or a battery?
Cell (+) ── Switch ── (−) · Closed Series Loop
9. For an electric current to flow and light up a bulb, what kind of path must the circuit form from one terminal of the battery to the other: a complete (closed) loop with no gaps, or a broken (open) loop?
Cell (+) ── Switch ── (−) · Closed Series Loop
10. In a standard circuit diagram, what component is represented by a circle with the letter “M” inside it: an electric motor or a buzzer?
Cell (+) ── Switch ── (−) · Closed Series Loop
11. In a parallel circuit, how does the total current leaving the battery compare to the currents in the individual parallel branches: the total current equals the sum of the currents in the branches, or the total current is zero?
Cell (+) ── Switch ── (−) · Closed Series Loop
12. 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
12 questions · Seed 104743 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 10-12
Conductors, insulators & circuits
Answers and reasoning. Review before teaching.
1. What circuit component allows current to flow in ONE direction only (and emits light when it is an LED): a diode (or light-emitting diode) or a fixed resistor?
Diode (or light-emitting diode)
A diode has low resistance in the forward direction and very high resistance in reverse.
2. 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.
3. 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.
4. What happens when you open (turn off) a switch in a simple series circuit: it creates a gap (open circuit) that stops the current flowing and turns the bulb off, or it makes the bulb brighter?
It creates a gap (open circuit) that stops the current flowing and turns the bulb off
A switch controls a circuit by safely opening or closing the conducting gap.
5. What happens if two identical cells in a torch are put in facing opposite directions (+ touching +): their voltages cancel out and the bulb will not light, or the bulb shines twice as bright?
Their voltages cancel out and the bulb will not light
Cells in series must be aligned positive-to-negative so their voltages add together.
6. Which circuit instrument is connected IN PARALLEL across a component to measure the potential difference (voltage) in volts (V): a voltmeter or an ammeter?
Voltmeter
A voltmeter has very high resistance and is connected across (in parallel with) a component.
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. In a standard circuit diagram, what component is represented by a circle with an “X” (cross) inside it: a filament lamp (bulb) or a battery?
Filament lamp (bulb)
A circle containing a cross is the standard circuit symbol for an indicator or lighting lamp.
9. For an electric current to flow and light up a bulb, what kind of path must the circuit form from one terminal of the battery to the other: a complete (closed) loop with no gaps, or a broken (open) loop?
A complete (closed) loop with no gaps
Current only flows around a continuous, closed conducting pathway.
10. In a standard circuit diagram, what component is represented by a circle with the letter “M” inside it: an electric motor or a buzzer?
Electric motor
A circle with an “M” represents an electric motor that converts electrical energy into kinetic rotation.
11. In a parallel circuit, how does the total current leaving the battery compare to the currents in the individual parallel branches: the total current equals the sum of the currents in the branches, or the total current is zero?
The total current equals the sum of the currents in the branches
By Kirchhoff’s current law (conservation of charge), current splits at a junction and recombines on return.
12. 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.
12 questions · Seed 104743 · Age guidance, not curriculum certification