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# Circuit Diagram LDR watch

1. Can someone show me what this would look like and explain it please?

Attachment 731190
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2. Dude, i think the upload of that attachment didn't work, as I can't see it, it may just be me tho
3. (Original post by m005eman)
Dude, i think the upload of that attachment didn't work, as I can't see it, it may just be me tho
Try looking on your phone if you aren’t already
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4. Since I don't want to give you the direct answer, treat the LDR as a normal resistor, and remember that R=V/I, hopefully you should be able to work it out from there, if not ask again, i'll try my best to help
5. (Original post by m005eman)
Since I don't want to give you the direct answer, treat the LDR as a normal resistor, and remember that R=V/I, hopefully you should be able to work it out from there, if not ask again, i'll try my best to help
Does the voltmeter measure potential difference and the ammeter measure the current? Do 2 components have to be placed in parallel or not? So I need a battery, voltmeter, ammeter, LDR, anything else? Also what do you mean by treating the LDR as a normal resistor?
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6. (Original post by Y11_Maths)
Does the voltmeter measure potential difference and the ammeter measure the current? Do 2 components have to be placed in parallel or not? So I need a battery, voltmeter, ammeter, LDR, anything else? Also what do you mean by treating the LDR as a normal resistor?
Yes that is all you need, and treat the LDR as any other resistor, because it doesnt matter what the object is your measuring, you're only interested in the resistance of a thing that resits, so its just a normal resistor as far as your concerned, and also in the placement of the components, think of kirchoff's laws (if you learn about them) it should give an indicator of where the components have to be placed
7. (Original post by m005eman)
Yes that is all you need, and treat the LDR as any other resistor, because it doesnt matter what the object is your measuring, you're only interested in the resistance of a thing that resits, so its just a normal resistor as far as your concerned, and also in the placement of the components, think of kirchoff's laws (if you learn about them) it should give an indicator of where the components have to be placed
I’ve never heard of Kirchhoff’s law but will check it out, thanks for helping
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8. (Original post by Y11_Maths)
Can someone show me what this would look like and explain it please?

Attachment 731190
ATTACHMENT NOT FOUND, otherwise I could help :|
9. (Original post by Mehru1214)
ATTACHMENT NOT FOUND, otherwise I could help :|
Try looking on our phone :?
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10. (Original post by Y11_Maths)
I’ve never heard of Kirchhoff’s law but will check it out, thanks for helping
Googling them can be a nightmare, as its used more in A level than GCSE, let me know if you understand them or not in relation to your question
11. (Original post by m005eman)
Googling them can be a nightmare, as its used more in A level than GCSE, let me know if you understand them or not in relation to your question
I sort of understand it but I don’t see how it’s related to this question sorry
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12. Thats ok, so lets take one of the laws, where all current into a point is equal to the current leaving that point, and also using the same law, we know that current is split when a parallel circuit is made. And so if an Ammeter measures current, then would it have to be placed in series or parallel to measure the current of the resistor?

And with the voltmeter, we know that with kirchoff's laws, that the total pd of a circuit is equal to the pd that is provided. But we also know that the voltage is split between components when they are in series, but is equal when in parallel. And so if the voltmeter is measuring this voltage, would it have to be placed in series or parallel to the resistor to measure the voltage across the resistor?

hope that helps further!

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