Behavior of a circuit when values increase or decrease

AI Thread Summary
The discussion focuses on how changes in resistor values affect current and power in a circuit. When R3 decreases, the current through R4 increases, but this also leads to a decrease in the current from the battery due to conservation of charge. A decrease in R1 results in an increase in current through R3 and R6. Conversely, if the voltage decreases, the total current from the battery decreases as well. The participants express confusion over the relationships and calculations, particularly regarding the impact of R3 on the overall current flow.
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Homework Statement


Consider the behavior of the circuit, when various values increase or decrease.
(Select I-increases, D-decreases, If the first is I and the rest D, enter IDDDDD).

A) If R3 decreases, the current through R4 ___.
B) If R3 decreases, the current from the battery ___.
C) If R1 decreases, the current through R3 ___.
D) If the voltage V decreases, the total current from the battery ___.
E) If R1 decreases, the current through R6 ___.
F) If R6 decreases, the power output from the battery ___.


Homework Equations


P = VI
V = IR


The Attempt at a Solution


A) I = V/(R3+R4+R5) so if R3 decreases, the current through R4 increases
B) If the current through R4 increases, the current through the battery decreases (conserved)
C) increases (because current from R1 increases)
D) V = IR, so if V decreases, I decreases
E) increases (same as C)
F) If R6 decreases, current increases, so power increases.

So, IDIDII. But this is wrong, and I'm not sure which one I'm not understanding correctly. The diagram is attached!
 

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B) If the current through R4 increases, the current through the battery decreases (conserved)

I don't know if this is correct. If you were to combine R3, R4 and R5 into one equivalent resistor, lowering R3 would lower the equivalent resistance, thus increasing current from the battery, so I think your part B is wrong. Although I could be wrong.
 
I understand what you are saying, but I tried IIIDII, and it's still wrong, so I think I'm still missing something...
 
A) If R3 decreases, the current through R4 ___.

Perhaps: If R3 decreases, more current would flow through R3, hence the current through R4 would decrease.
 
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