Engineering, 26.02.2020 05:55 bankscorneliuso39

Now design a BJT circuit which turns a red LED on when the room lights are off.
Conversely, the LED should extinguish when the room is lit again. (Cup your handsaround the circuit to simulate darkness.)

You will need a light-sensitive resistor for this design.

A cadmium sulfide (CdS) photocell has a low resistance when exposed to light (typically 1-4 k) and a high resistance in darkness (typ. 50k-100 k).

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Now design a BJT circuit which turns a red LED on when the room lights are off.
Conversely, t...

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