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Multiple-Choice Homework Problem 15.6 The figure to the right shows a junction i

ID: 1433084 • Letter: M

Question

Multiple-Choice Homework Problem 15.6 The figure to the right shows a junction in a larger circuit. The currents flowing into and out of the junction are labeled. What is the current flowing in the leg labelled with the question mark? Select One of the Following: (a) 1A (b) 2A (c) 12A (d) 16A (e) 20A

Multiple-Choice Homework Problem 15.7 Suppose the electric field was not perpendicular to the surface of a conductor, what would happen? Select One of the Following: (a) Nothing would happen if the field was not perpendicular to the conductor’s surface. (b) The electric field would be larger inside the conductor than outside the conductor. (c) An electric current would flow along the surface of the conductor. (d) The surface atoms of the conductor would become insulating. (e) The resistance of the conductor would increase.

Multiple-Choice Homework Problem 15.8 The figure below shows a circuit that is part of a larger circuit. Select the loop equation for the loop drawn (Loop abcda) using the current directions introduced on the figure. Select One of the Following: (a) I2R2 + ?V2 + I1R1 + ?V1 = 0 (b) ?I2R2 + ?V2 ? I1R1 + ?V1 = 0 (c) I2R2 ? ?V2 + I1R1 ? ?V1 = 0 (d) I1R2 + ?V2 + I2R1 + ?V1 = 0 (e) I2R2 + ?V2 + I3R1 + ?V1 = 0 (f) I1R2 ? ?V2 + I2R1 ? ?V1 = 0 (g) ?I3R2 + ?V2 ? I1R1 + ?V1 = 0 (h) ?I2R2 + ?V2 ? I3R1 + ?V1 = 0

Multiple-Choice Homework Problem 15.9 A uniform surface charge lies in the x ? y plane. Above the plane, the electric field is E~ above = ?500.0N/Cˆz. Below the plane, the electric field is E~ below = +200.0N/Cˆz, so both fields point toward the plane. Note, the system must be part of a larger system since the outer field is not equal but opposite. Compute the surface charge density of the plane. Select One of the Following: (a) 6.2 nC m2 (b) ?6.2 nC m2 (c) +2.7 nC m2 (d) ?2.7 nC m2 (e) 0

Multiple-Choice Homework Problem 15.10 Two infinite parallel planes of fixed charge density ? and ?3? are held a distance d apart as shown in the figure to the right. A neutral conducting slab of thickness d/2 is inserted between the plates. Compute the magnitude of the potential difference between the plates. Select One of the Following: (a) |?V | = ?d/?0 (b) |?V | = 2?d/?0 (c) |?V | = ?d/2?0 (d) |?V | = 4d?/?0 (e) |?V | = 5?d/2?0

Explanation / Answer

Doing first 3 parts

for 15.6

net current in node=0 A

let current is x A

9-7-x=0

x=2A flowing out

option (b) is correct

15.7

(c) An electric current would flow along the surface of the conductor.

15.8

By KVL

I2R2 + V2 + I1R1 + V1 = 0

option (a) is correct