Question 1

Given three resistors $$R_1$$, $$R_2$$, and $$R_3$$ connected in series as shown in the first image, which of the following statements is correct about the current and voltage in the circuit?

Accepted Answer

The current is the same through each resistor, but the voltage across each may be different.

Question 2

For the parallel circuit shown in the second image, what is the correct formula for the equivalent resistance $$R_{eq}$$?

Accepted Answer

$$\frac{1}{R_{eq}} = \frac{1}{R_1$} + \frac{1}{R_2$} + \frac{1}{R_3$}$$

Question 3

In the circuit with three identical light bulbs (third image), which bulb is the brightest and why?

Accepted Answer

Bulb A, because it receives the full current from the battery.

Question 4

If more resistors are added in parallel between points $$P$$ and $$Q$$, what happens to the total resistance?

Accepted Answer

It decreases.

Question 5

A battery of $$\mathcal{E} = 60\ 	ext{V} is $$connected to two resistors in parallel: $$R_2 = 20$$\ \Omega$$ and R_3$ = 30\ \Omega. $$What is the total current supplied by the battery?

Accepted Answer

$$5\ 	ext{A}$$

Question 6

Given $$R_1 = 10$$\ \Omega$$, R_2$ = 20\ \Omega$$, $$R_3 = 30$$\ \Omega$$, and $$\mathcal{E} = 44\ 	ext{V}$$, with R_2$ and R_3$ in parallel and R_1$ in series with them, what is the current through R_2$?

Accepted Answer

$$1.2\ 	ext{A}$$

Question 7

Which of the following best describes a 'branch' in an electric circuit?

Accepted Answer

A single path connecting two nodes, containing a circuit element like a resistor or capacitor.

Question 8

According to Kirchhoff’s Junction Rule, what must be true at any junction in a circuit?

Accepted Answer

The sum of the currents entering equals the sum of the currents leaving.

Question 9

In the fifth image, what is the magnitude and direction of the current in the fourth wire (horizontal, to the left)?

Accepted Answer

$$2\ 	ext{A} to $$the right

Question 10

Kirchhoff’s Loop Rule is based on which fundamental physical principle?

Accepted Answer

Conservation of energy

Question 11

When traversing a resistor in the direction of current, what is the sign of the potential change according to the sign conventions (last image)?

Accepted Answer

It is negative.

Question 12

A circuit contains two batteries and two resistors in series. If you traverse the loop in the direction of current, how do you write the loop equation?

Accepted Answer

$$+\mathcal{E}_1 - I R_1$ - I R_2$ - \mathcal{E}_2 = 0$$

Question 13

Which of the following is NOT a correct step in analyzing a multi-loop circuit using Kirchhoff’s Rules?

Accepted Answer

Assume all currents flow in the same direction in every branch.

Question 14

A real-world application: In a household circuit, why are most appliances connected in parallel rather than in series?

Accepted Answer

Because parallel connections ensure each appliance receives the same voltage.

Question 15

If a voltmeter is connected across a resistor in a circuit, what does it measure?

Accepted Answer

The potential difference (voltage) across the resistor.

Question 16

A $$12\ \Omega$$ and a $$6\ \Omega$$ resistor are connected in parallel. What is their equivalent resistance?

Accepted Answer

$$4\ \Omega$$

Question 17

Which of the following best describes the effect of adding more branches (resistors in parallel) to a circuit?

Accepted Answer

The total current from the battery increases.

Question 18

A circuit contains a battery of $$\mathcal{E} = 24\ 	ext{V}$$ and three resistors in series: $$R_1 = 2$$\ \Omega$$, R_2$ = 4\ \Omega$$, $$R_3 = 6$$\ \Omega$$. What is the current in the circuit?

Accepted Answer

$$1\ 	ext{A}$$

Question 19

Which of the following is a correct application of the conservation of charge at a junction, as shown in the fourth image?

Accepted Answer

$$I_1$$ = $$I_2$$ + $$I_3$$

Week 5 Lec. 1

Study Guide - Practice Questions

Study Guide - Flashcards