Contents
Key Stage 2
Meaning
A circuit is a loop of wire that electricity flows around.
About Circuits
- A circuit needs to be complete otherwise electricity will not flow through it. Any break in the circuit will stop the electricity from flowing.
- A circuit starts and ends at the source of power. This is usually a battery or cell but it can be a generator or Solar Cell.
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| A circuit must be a complete loop without any breaks or it will not work. | The break in this circuit stops it from working. |
To practice building a circuit you can use a circuit simulator by clicking on the picture below.
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Key Stage 3
Meaning
A circuit is a loop of wire that electricity flows around.
About Circuits
- Circuits can have components in series or parallel.
- Components in parallel in a circuit have the same Potential Difference across them but share the Current.
- Components in series in a circuit have the same Current through them but share the Potential Difference.
Examples
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| The bulb and Ammeter are in series so they have the same Current going through them. | The cell, bulb and Voltmeter are in parallel so they have the same Potential Difference across them. | The two bulbs are in parallel so they have the same Potential Difference across them but may have a different Current passing through them. |
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| The motor and resistor are in series so they have the same Current passing through them but share the 1.5V Potential Difference between them. | The bulb and motor are in parallel so they have the same Potential Difference across them but may have a different Current passing through them. | The motor, resistor and bulb are in series so they all have the same Current passing through them but share the 1.5V Potential Difference between them. |
Energy Transfers
Cell
- Energy is transferred electrically out of the chemical potential energy store.
Light Bulb
- Energy is transferred electrically into the the thermal energy store of the bulb.
- Energy is also transferred away from the bulb by light radiation.
Motor
- Energy is transferred electrically into the the kinetic energy store of the motor as it speeds up.
- Energy is transferred electrically into the the thermal energy store of the motor due to friction.
Speaker or Buzzer
- Energy is transferred electrically into the the kinetic energy store of the Speaker.
- Energy is also transferred away from the Speaker by sound radiation.
Key Stage 4
Meaning
A circuit is a loop of wire that electricity flows around.
About Circuits
- Circuits can have components in series or parallel.
- Components in parallel in a circuit have the same Potential Difference across them but share the current.
- Components in series in a circuit have the same Current through them but share the potential difference.
Examples
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| This circuit can be used to plot the IV Graph for a diode. | This circuit can be used to activate a lamp when it is dark. | This circuit can be used to find the resistance of a wire. |
Energy Transfers
Cell
- Energy is transferred electrically out of the chemical potential energy store.
Light Bulb
- Energy is transferred electrically into the the thermal energy store of the bulb.
- Energy is also transferred away from the bulb by light radiation.
Motor
- Energy is transferred electrically into the the kinetic energy store of the motor as it speeds up.
- Energy is transferred electrically into the the thermal energy store of the motor due to friction.
Electrical Heater
- Energy is transferred electrically into the the thermal energy store of the heater.
Speaker or Buzzer
- Energy is transferred electrically into the the kinetic energy store of the Speaker.
- Energy is also transferred away from the Speaker by sound radiation.