Physics 2213
Homework #6
Spring 2009
Read:
Chapter 24, intro., sections 24.1 thru 24.5
Chapter 26, section 26.4
Learning Goals:
(Be sure you understand where and how each goal in each assignment applies to our
homework, discussion, lecture, and lab activities.)
*
Explain what a capacitor is and calculate how its electrical properties are related — charge,
voltage, stored energy, capacitance, electric current.
*
Show how to calculate the capacitance of a parallel plate capacitor, given its geometry.
*
Use the parallel plate capacitance expression to approximate the capacitance of real systems.
*
Explain why electric charge is distributed the way it is in capacitors.
*
Explain how and why the capacitance of a capacitor is affected by the presence of a
dielectric insulator filling the space between the capacitor's plates, and calculate such effects.
*
Explain and calculate how energy is stored in a capacitor.
*
Explain how a capacitor functions in an electric circuit.
*
Predict and calculate the time-dependent behavior of RC circuits containing resistors,
capacitors, DC power supplies, and switches.
Draw graphs showing the time dependence of
electrical quantities such as voltages, currents, and charges in these circuits.
*
Show how to reduce appropriate networks of capacitors to equivalent simpler forms using
series and parallel combinations.
For extra practice:
Chap. 24: Q's #Q24.1, 4-9, 11-13, 15, 18, 20
E's & P's: #24.7, 15, 21, 27, 37, 59a, 65a, 77
Chap. 26: Q's #Q26.19-21
E's & Ps: #26.41, 49, 87
To be prepared for Wednesday-Friday, Mar. 4-6 at your 2nd weekly Discussion section:
#24.14
[Capacitor Network]
#24.66
[Capacitor + Metal Slab]
1.
["Build-a-Cap"]
A capacitor is constructed out of
two sheets of aluminum foil and three sheets of paper in
the form of a double-decker sandwich, as shown.
The
foil sheets are 17 cm x 24 cm in size and 0.050 mm thick,
while the paper sheets are 21cm x 28 cm in size and