212 - Problem Set 5

Physics 212 Fall 2008 Problem Set #6 Due Friday, October 3rd

Review: 18.2 and lecture notes then do the problems. 1)

Analyze the circuit below using a V-I-R chart. R4

Values R1 = 20 Ω R2 = 3.0 Ω 20 V R3 = 4.0 Ω R4 = 9.0 Ω R5 = 8.0 Ω R6 = 6.0 Ω 2)

R2

12 V R4

R1

R5 R6

6)Find the current through the 12 Ω resistor in the circuit below.

Analyze the circuit below using a V-I-R chart.

Values R1 = 3.0 Ω R2 = 10.0 Ω R3 = 5.0 Ω R4 = 4.0 Ω R5 = 3.0 Ω

3)

R4

R2 R1 R3

R5

40 V

R1

R4

R1

R5 R7 R6

18 V

The voltage between the terminals of the battery is observed to be 8.3 V. Find the internal resistance of the battery.

R3 8)

R2 R6

R2

7)A 1.4 Ω resistor is connected across a 9 V battery.

R4 15 V

R3

Values R1 = 3.0 Ω R2 = 3.0 Ω R3 = 6.0 Ω R4 = 6.0 Ω R5 = 4.0 Ω R6 = 12.0 Ω R7 = 2.0 Ω

Analyze the circuit below using a V-I-R chart.

Values R1 = 6.0 Ω R2 = 6.0 Ω R3 = 2.4 Ω R4 = 6.0 Ω R5 = 9.0 Ω R6 = 6.0 Ω

R5

R3

R5

From the information given in the circuit below, (a) determine the current in the circuit, and (b) state which point, A or B, is at a higher potential. 5Ω 27 Ω A 30 V

4)In the circuit below, the current through R

8Ω 4

is 0.5 A. Find the

12 Ω

10 V

B

current through (a) R5 and (b) R2. R4

9)Calculate the unknown

R5

Values R1 = 18.0 Ω R2 = 9.0 Ω R3 = 16.0 Ω R4 = 8.0 Ω R5 = 20.0 Ω

R3

2Ω

currents I1, I2, and I3 for the circuit below.

R2

24 V

R1

4Ω

I1

1Ω

I3

3Ω I2

ANSWERS: 1) Req=4.6 Ω 2) Req=5.13 Ω 3) Req=15 Ω Values 4) a) 0.75 A, b) 2.11 A

12 V 5) 6) 7) 8)

2.22 W 0.429 A 0.12 Ω 0.38 A

9) I1 = 3.5 A I2 = 1.0 A I3 = 2.5 A

R = 4.0 Ω 5)Determine R = 2.0 Ωthe power dissipated in R 1 2

R3 = 1.0 Ω R4 = 5.0 Ω R5 = 1.0 Ω

4

R2 R1

in the circuit below. R3

5Ω