PHYS 210 Saint Marys University of Minnesota AC Circuit Physics Problem Set 9 Hello, I need your help on a homework about AC circuit in Physics. There are

PHYS 210 Saint Marys University of Minnesota AC Circuit Physics Problem Set 9 Hello, I need your help on a homework about AC circuit in Physics. There are 4 questions on this homework. You can either do it by handwriting and scan it, or you can do it in Word document. All the instruction is on the pdf document call “ps9.pdf”. Thanks Physics 210: Problem Set 9
Due Date: April 17, 2020
1. Consider a series circuit with a resistor, a 1.4 H inductor and a 60 Hz generator. The rms
voltage across the resistor is 30 V and the rms voltage across the inductor is 40 V. (a) Find
the resistance of the resistor (b) Find the peak voltage of the generator.
2. Consider a resistor and inductor connected in parallel across an ideal ac source with an
output of E = Emax cos ωt as shown below. (a) Show that the current in the resistor is
IR = (Epeak /R) cos ωt (b) the current in the inductor is IL = (E/XL ) cos(ωt − 90) (c) the
current in the voltage source is I = IR + IL = (E/Z) cos(ωt + δ)
L
R
E
3. Consider the portion of the circuit below where an inductor (L = 2 mH) and capacitor
is connected in series. The capacitor has a width of w = 20 cm and a gap of 2 mm. A
dielectric with dielectric constant of 4.8 is slid back and forth in the gap between the parallel
plate capacitors. If x = w/2 (dielectric is half-way), then the resonant frequency is 90 MHz.
(a) Find the capacitance of the capacitor without an dielectric (b) Find the resonant frequency
for any value of x, i.e., 0 < x < w. w x L 4. In class, we showed that a RLC circuit is governed by the equation L dQ Q d2 Q +R + =0 2 dt dt C Showp by direct substitution that Q(t) = Q0 exp(−t/τ ) cos(ω 0 t) solves this equation, where ω 0 = 1/(LC) − 1/τ 2 and τ = 2L/R 1 Purchase answer to see full attachment