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Potential divider

  • #1
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Homework Statement



http://puu.sh/dzujr/dcf208c4a5.png [Broken]

Homework Equations


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

The Attempt at a Solution


When there is low light, resistence 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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Answers and Replies

  • #2
CWatters
Science Advisor
Homework Helper
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This isn't really "advanced" physics (so the moderators might move it to another sub forum) but..

When there is low light, resistence 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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