lesson
A lamp needs a complete circuit
1 · Learn
A simple circuit can contain a cell, wires and a lamp. The lamp lights when it is correctly connected in a complete conducting loop to the cell and the components work together.
Connecting just one lamp terminal leaves a gap. A wire touching the glass is not the same as connecting the correct metal contact. Draw each connection clearly so you can trace the loop.
2 · Worked example
I trace from one cell terminal through a wire, the lamp and another wire to the other terminal. If a connection is missing, the loop is incomplete.
3 · Your turn
A wire comes loose from the lamp's contact. Why might the lamp go out?
Check your answer
The conducting loop is broken, so the complete circuit needed to light the lamp is no longer present.
4 · Apply your learning
With a supervising adult, build one simple circuit using an approved classroom kit and matching components. Draw the actual connections.
Adult guidance and safety
Use only adult-approved low-voltage cells and holders. Never mains power, loose button cells, damaged batteries or direct wire-to-wire short circuits. Disconnect if anything warms.
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