Problem: Consider the circuit shown. (Intro 1 figure) All wires are considered ideal; that is, they have zero resistance. We will assume for now that all other elements of the circuit are ideal, too: The value of resistance is a constant, the internal resistances of the battery and the ammeter are zero, and the internal resistance of the voltmeter is infinitely large.Intro 1:Intro 2:Part A What is the reading V of the voltmeter?Express your answer in terms of the EMF ℰ. Part BThe voltmeter, as can be seen in the figure, is connected to points 1 and 3. What are the respective voltage differences between points 1 and 2 and between points 2 and 3?a) 0; ℰb) 0; -ℰc) ℰ; 0d) ℰ;ℰPart CWhat is the reading I of the ammeter?Express your answer in terms of ℰ and R.Now assume that the battery has a nonzero internal resistance r (but the voltmeter and the ammeter remain ideal). (Intro 2 figure)Part DWhat is the reading of the ammeter now?Express your answer in terms of ℰ, r, and R.Part EWhat is the reading of the voltmeter now?Express your answer in terms of ℰ, r, and R.

FREE Expert Solution

Part A 

Kirchoff's loop rule:

ΣV=0

V = ε - IR

There is no resistance across points 1 and 3. Due to the very large resistance across the voltmeter, V, no current flows in the voltmeter. 

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Problem Details

Consider the circuit shown. (Intro 1 figure) All wires are considered ideal; that is, they have zero resistance. We will assume for now that all other elements of the circuit are ideal, too: The value of resistance is a constant, the internal resistances of the battery and the ammeter are zero, and the internal resistance of the voltmeter is infinitely large.

Intro 1:

Intro 2:

Part A 

What is the reading V of the voltmeter?

Express your answer in terms of the EMF ℰ. 

Part B

The voltmeter, as can be seen in the figure, is connected to points 1 and 3. What are the respective voltage differences between points 1 and 2 and between points 2 and 3?

a) 0; ℰ

b) 0; -ℰ

c) ℰ; 0

d) ℰ;ℰ

Part C

What is the reading I of the ammeter?

Express your answer in terms of ℰ and R.

Now assume that the battery has a nonzero internal resistance r (but the voltmeter and the ammeter remain ideal). (Intro 2 figure)

Part D

What is the reading of the ammeter now?

Express your answer in terms of ℰ, r, and R.

Part E

What is the reading of the voltmeter now?

Express your answer in terms of ℰ, r, and R.

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