There are 15 identical decorative LEDs connected in series with a 12 V power supply.
What is the voltage across each LED in the series circuit?
Each LED has a power of 2.0 W. State the equation linking power, current, and voltage.
Show that the current in the circuit is 2.5 A.
The LEDs are switched on for 6 hours a day for 4 days. Calculate the total energy transferred during this time in joules (J).
Describe the main energy transfers that take place in each LED when they are connected to the power supply.
25 exam-style questions on Edexcel IGCSE Physics Energy and voltage in circuits. Each one has a worked solution and a mark scheme showing where the marks go.