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Name: Maliha
Status: Student
Age: 14
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What kind of circuit would a burglar alarm that causes lights to open, bell to ring, and a trap door to open look like?

Not different from a switch that causes these things to happen, though a burglar alarm would probably include a latch to keep the bell ringing after the alarm had been tripped.

A latch could simply be a relay, part of whose switched current is diverted to supplement its control current. These days, it would more likely be implemented with a TTL flip-flop.

Tim Mooney

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