Potential Divider: R(R+r)*E=V - Wrong Ans Explained

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The discussion revolves around the potential divider equation R(R+r)*E=V, specifically in the context of a light-dependent resistor (LDR) and a thermistor. When light levels are low, the resistance of the LDR increases, leading to a higher voltage across it and a lower voltage across the thermistor, which is associated with lower temperatures. The initial conclusion that the answer is B is challenged, as increased light decreases the LDR's resistance, raising the output voltage. This clarification narrows the possible answers to B or D, prompting further examination of the thermistor's behavior in this scenario. The conversation highlights the importance of understanding how both components interact under varying light conditions.
Arun Raja
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Homework Statement



http://puu.sh/dzujr/dcf208c4a5.png

Homework Equations


Potential divider concept--> R(R+r)*E=V

The Attempt at a Solution


When there is low light, resistance of LDR increase to produce light.

So, voltage across LDr increases and voltage across thermistor decrease-->lower temperature

so I think answer B , but it is wrong
 
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This isn't really "advanced" physics (so the moderators might move it to another sub forum) but..

Arun Raja said:
When there is low light, resistance of LDR increase [strike]to produce light[/strike].

That first part is correct. More light (high illumination) causes the resistance of the LDR to fall. That will tend to "pull" the output voltage higher. That reduces your choices to B or D.

Now what about the thermistor?
 
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