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2 topics

By subject and area, youngest first

  • Electronics // Circuits

    Ohm's law

    For a resistor, voltage equals current times resistance (V = I × R). Rearranging it gives the current a circuit will draw or the resistor a part needs.

    Ages 12 to 15Method

  • Electronics // Components

    Light-emitting diodes

    An LED lights when current flows through it one way, from the longer leg to the shorter. It needs a resistor in series so the current stays small enough not to…

    Ages 11 to 14Method