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aamc 4 problem 41 on the ps section
which of the following changes to the circuit will decrease the electric field between the electrodes by the greatest amount.
the circuit consists of a resistor and capacitor (resistor is a at a higher potential/before the capacitor)
answer: increasing d (distance between plates) by a factor of 2
explanation: for a fixed voltage between the cathode and anode, the electric field is inversely proportional to the distance between them. increasing the circuit resistance for a fixed current will decrease the electric field, but not by as much as does the length change
E= (V-IR)/L
so my question is: how come the current is considered constant. doesn't the current go down if the resistance of the circuit goes up?
which of the following changes to the circuit will decrease the electric field between the electrodes by the greatest amount.
the circuit consists of a resistor and capacitor (resistor is a at a higher potential/before the capacitor)
answer: increasing d (distance between plates) by a factor of 2
explanation: for a fixed voltage between the cathode and anode, the electric field is inversely proportional to the distance between them. increasing the circuit resistance for a fixed current will decrease the electric field, but not by as much as does the length change
E= (V-IR)/L
so my question is: how come the current is considered constant. doesn't the current go down if the resistance of the circuit goes up?