ECE 3364, Dr. Hebert, Spr 2009 Homework 1, Due Mon 2/2
Problem 1.
(a) What is "energy"?
(b) What is "power"?
(c) How are power and energy related?
Problem 2.
Given an RLC circuit in steady-state with a sinusoid forcing function, plot the
instantaneous power absorbed by an inductor over two periods of the sinusoid Tt 20 ≤≤ .
Use )
2
sin()( t
T
Iti mL
π
= .
Problem 3.
Given an RLC circuit in steady-state with a sinusoid forcing function, plot the
instantaneous power absorbed by a capacitor over two periods of the sinusoid Tt 20 ≤≤ .
Use )
2
sin()( t
T
Iti mC
π
=
Problem 4.
Nilsson, seventh edition
Problem 10.3
Problem 5.
Nilsson, seventh edition
Problem 10.6
Problem 6.
Nilsson, seventh edition
Problem 10.14
Hint: parts (a) and (b) are about instantaneous power delivered/absorbed by the voltage
source. The load is a parallel R and C. The voltage source delivers a non-negative power
p(t)= v(t)*i(t) to the resistor at all values of time. But the voltage source delivers power to
the capacitor at certain times, and the rest of the circuit absorbs power back from the
capacitor at other times. Mathematically, this is seen when you form p(t)= v(t)*i(t) where
v(t) and i(t) are sinusoids of the same freq, but i(t) has a phase shift wrt (with respect to)
v(t). When you apply a trig identity to the product cos(a)*cos(b), you will get a sinusoid
with a DC offset.