Behavior of a circuit when values increase or decrease

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SUMMARY

The discussion focuses on the behavior of a circuit in response to changes in resistance values. Specifically, when resistance R3 decreases, the current through R4 increases, while the current from the battery decreases due to conservation of charge. Conversely, a decrease in R1 results in an increase in current through R3 and R6. The relationship between voltage and current is highlighted, indicating that a decrease in voltage leads to a decrease in total current from the battery. The final conclusion is that the initial assessment of current behavior was incorrect, particularly regarding the impact of R3 on the battery current.

PREREQUISITES
  • Understanding of Ohm's Law (V = IR)
  • Knowledge of power calculations (P = VI)
  • Familiarity with circuit analysis techniques
  • Basic concepts of current conservation in electrical circuits
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  • Learn about Kirchhoff's laws for current and voltage in circuits
  • Explore the impact of varying resistance on circuit behavior using simulation tools like LTspice
  • Investigate the relationship between power, voltage, and current in more complex circuits
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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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