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physics gsce question

the specification for psychic says that the 'resistance of an LDR decreases when the light intensity increase.....eg. switching on lights on when it gets dark'

But that doesn't make senes, as if its resistance decreases at a higher light intensity, than means a higher voltage so bright light when its lighter? so confused. I would appreciate someone helping me out... I have mocks VERY soon and I'm basically cramming lol


thank you so much xxx
Original post by vix.xvi
the specification for psychic says that the 'resistance of an LDR decreases when the light intensity increase.....eg. switching on lights on when it gets dark'

But that doesn't make senes,

You use the LDR as part of a switching circuit rather than directly in series with a light bulb.

https://www.electronics-notes.com/articles/electronic_components/resistors/light-dependent-resistor-ldr.php

E.g. lots of light makes the LDR conduct, and you use that to turn OFF a transistor that controls a lighting system, for example in the circuit linked below, the LDR controls the voltage at the base of a transitor, turning it on as the resistance goes up.

https://www.instructables.com/id/How-to-Make-LDR-Darkness-Sensor-Circuit-Simple-DIY/
Original post by Mr Wednesday
You use the LDR as part of a switching circuit rather than directly in series with a light bulb.

https://www.electronics-notes.com/articles/electronic_components/resistors/light-dependent-resistor-ldr.php

E.g. lots of light makes the LDR conduct, and you use that to turn OFF a transistor that controls a lighting system, for example in the circuit linked below, the LDR controls the voltage at the base of a transitor, turning it on as the resistance goes up.

https://www.instructables.com/id/How-to-Make-LDR-Darkness-Sensor-Circuit-Simple-DIY/

ohhh wow that makes sense tysm!

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