W10D2 CAPACITORSChapter 20 Materials

TOPICS FOR THE NEXT WEEK

Wednesday (Today) Don’t miss the new WA that has been posted. Today we work on Capacitors from Chapter 20 Look at the chapter – we have already covered a lot of

it! Watch for another WA later in the week on this material.

Friday Quiz #4 The Evan Show Complete the chapter

Monday – Probably start the next chapter.

FINAL EXAM SCHEDULE

http://www.registrar.sdes.ucf.edu/calendar/exam/2011/fall/ (on class website) Cut & Past – Link doesn’t work.

Check for conflicts on Saturday, 12/3. If we can’t do that we will do Saturday, 12/10 (yuck).

If I don’t hear from you, we will go ahead with the schedule determination. No make-up exam will be offered if you can’t

make the final at that time.

SEMICONDUCTORS

ALL BECAUSE SOMEONE ASKED

Electron and hole mobility versus temperature. The doping density equals 1016 (top curve), 1017 and 1018 (bottom curve) cm-3. (For Silicon … JBB)

Find the power output of a battery with an emf of 1.6 V generating a current of 6 A (essentially the short circuit or maximum current for one of our batteries).

A) 9.6 WB) 6 WC) 1 WD) 1.6 W

A 60 W bulb (240 Ohms) and a 75W (192Ohms) bulb are in series connected to a 120 volt wall socket. Which bulb will be brighter?

a. 60Wb. 75Wc. They use the same power

since they have the same current flowing through them

d. Can’t tell from this info

CALCULATION

A 60 W bulb (240 Ohms) and a 75W (192 Ohms) bulb are in series connected to a 120 volt wall socket. Which bulb will be brighter?

120 (given)

T 240 192 432

120 / 432 0.28

total

total

V V

I A

260 60

2 275 75

18.8

192 15

Power to the 60!

P I R Watt

P I R I x Watt

More

Two resistors R1=300 Ohms and R2=200 Ohms are in parallel connected to a 12 volt battery. Which resistor is using more power?

a. R1b. R2c. They use the same power since they have the same current flowing through

themd. Can’t tell from this info

2

Same Voltage (Parallel)

Smaller R is Bigger Power!

VP

R

A B

C D

Consider the circuit diagram – when the circuit is completed (t=0) which graph represents the current that flows in the circuit as a function of time?

Fromthe

readingassignme

nt!

A B

C D

Which graph shows the MAGNITUDE of the chargeon the RIGHT plate as a function of time from switch on?

Last One!