Problem set #4, EE 223, 2/06/2003 – 2/13/2003
Chapter 9, Problem 23.
After being open for a long time, the switch in the
circuit of Fig. 9.38 is closed at t = 0.
For t > 0, find (a) vC(t); (b) iSW(t).
Chapter 9, Problem 47.
Find is(t) for t > 0 in the circuit of Fig. 9.51 if vs(t)
equals (a) 10u(-t) V; (b) 10u(t) V.
Chapter 9, Problem 49.
The current source in the circuit of Fig. 9.53 suddenly
increases from 15 A to 22 A at t = 0.
Find the voltage vs at
(a) t = 0-; (b) t = 0+; (c) t = ∞; (c) t = 3.4 s.
Verify your answers with the appropriate PSpice
simulations.
Chapter 11, Problem 17.
Find the value of RL in the circuit of Fig. 11.34 that
will absorb a maximum power, and specify the value
of that power.
Chapter 11, Problem 43.
Find the complex power being delivered to a load that
(a) draws 500 VA at a leading PF of 0.75;
(b) draws 500 W at a leading PF of 0.75;
(c) draws -500 VAR at a PF of 0.75.
Chapter 11, Problem 45.
A source of 230 V rms is supplying three loads in parallel:
1.2 kVA at a lagging PF of 0.8, 1.6 kVA at a lagging PF of 0.9, and 900 W at unity PF.
Find (a) the amplitude of the source current; (b) the PF at which the source is operating;
(c) the complex power being furnished by the source.