"AND" and "OR" switches

Curricula: KS2, Sek I, cycle 4

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Aim

Make a table showing when the lamp is lit for two switches connected in series and in parallel.

The bench

Two circuits with 4.5 V sources and 4.5 V / 1 W lamps. At the top is "AND": two switches in series, the first closed, the second open, the lamp is off. At the bottom is "OR": two switches in parallel branches, the lower one open, the upper one closed, the lamp is lit.

Procedure

1. In the top circuit, go through all four positions of the two switches and write down when the lamp is lit.
2. Do the same in the bottom circuit.
3. Put the results in a table: switch 1, switch 2, lamp.

Expected result

At the top the lamp is lit only when both switches are closed ("AND"). At the bottom it is lit when at least one is closed ("OR").

Questions

1. Which connection is suitable for a press that switches on only with both hands at once?
2. Which one is suitable for a bell that can be switched on from two rooms?

Answers

1. Two switches in series, "AND". The press starts only when both switches are closed, one under each hand, so both hands are away from the press while it works.
2. Two switches in parallel, "OR". Closing either switch is enough to ring the bell, so it can be rung from each room.