W9_parallel_resonance.eps

Week 5: Resistance 191

Problem 4.

+Qo

S

C

R

Suppose switchSis closed at timet= 0 when the charge on the capacitor isQ 0. FindQ(t),I(t),
VC(t) andVR(t) in the circuit above. Find the power delivered to the resistor as a function of time
and show that its integral from 0 to∞equals the initial energy stored on the capacitor (verifying
energy conservation for this circuit).

Problem 5.

Vo

S

R

C

Suppose switchSis closed at timet= 0 when the charge on the capacitor isQ 0 = 0. FindQC(t),
I(t),VC(t) andVR(t) in the circuit above. Find the power delivered to the circuit as a function of
time and show that it equals the sum of the power being burned in the resistor plus the power that
is charging the capacitor (verifying energy conservation for this circuit).