How does Kirchhoff's Loop Rule apply to an AC generator with a resistor?

AI Thread Summary
Kirchhoff's Loop Rule can be applied to an AC generator connected to a resistor by establishing the relationship E_m sin(w_d t) = R dQ(t)/dt, leading to a differential equation. By substituting dQ/dt with the current I, the equation simplifies to I = E_m sin(w_d t) / R. For a resistor of 50 Ohms and a maximum EMF of 30.0 V, the amplitude of the alternating current can be calculated as 30.0 V / 50 Ohms. The frequency of the EMF at 1.00 kHz does not alter the amplitude calculation directly in this context. This discussion highlights the application of Kirchhoff's Law in AC circuits and the derivation of current from voltage and resistance.
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Homework Statement



A resistor of resistance R is connected to an AC
generator with EMF(t)=(EMF_max)sin((w_d)t). (a) Write
Kirchhoff's Loop Rule for this circuit at a particular
instant of time. Is your result a differential equation?
(b) Find the current as a function of time. Now assume
R=50 Ohm and EMF_max = 30.0 V. (c) What is the amplitude
of the resulting alternating current if the frequency of
the EMF is 1.00 kHz?

Homework Equations



V_R = R dQ(t)/dt

The Attempt at a Solution



Ok, so the differential equation I came up with is:
V_G + V_R = 0
E_m sin(w_d t) = R dQ(t)/dt

assuming that's correct how do I find the current as a function of time? Replace dq/dt with i? And after that?
 
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And after that u get equation E_m sin(w_d t)=R I, hence I=\frac {E_m sin(w_d t)}{R} and the amplitude of the ac current is \frac{E_m}{R}

Something else, usually we apply Kirchoff's Law with currents and voltages and not with charges Q. Therefore MAYBE the correct answer to a) is by having replace dq/dt with I from the start and therefore the equation isn't a differential equation.
 
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Perfect, thank you!
 
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