chapter 13-electric circuits

A 10 Ω resistor and a 20 Ω resistor are connected in series in a closed circuit with a 3.0 V battery. Assuming negligible internal resistance in the battery, the current in the 10 Ω resistor will equal______A and the current in the 20 Ω resistor will equal_____A

0.1 0.1

Suppose you have three resistors with resistances of 2 Ω, 5 Ω, and 10 Ω (one of each).The smallest value that you can make using any combination of one or more of them is___Ω

1.25Ω.

The voltage drop across a resistor is 6.0 V when a current of 3.0 A flows across the resistor. The current that will produce a voltage drop of 5.0 V across the resistor is_____A

2.5

According to Ohm's law, the potential difference required to pass a current of 0.5 A in a wire of resistance 40 Ω is____V

20 (40Ω *0.5A)

The resistance of an electric bulb drawing 0.4 A current at 1.2 V is _________Ω.

3(1.2/0.4=3)

Select all that apply Which of the following are essential elements of an electrical circuit?

A closed path A source of electricity

You have two old pieces of equipment with no clear markings, so you label one meter A and the other meter B. You know that one is an ammeter and one is a voltmeter, but you do not know which is which. You measure the resistance of each, finding that meter A has a resistance of 3000-Ω, and meter B has a resistance of 0.10-Ω. You can conclude that

A is the voltmeter, and B is the ammeter.

A battery provides the energy needed to move electrical charges through a circuit. Where does the energy for the battery come from?

Chemical reactions

What is the best way to ensure that a 40-W bulb, a 60-W bulb, and a 70-W bulb have the same voltage applied to them in a circuit?

Connect all three bulbs in parallel.

Select all that apply You have a 1.5-V flashlight battery, a 10-Ω resistor, a 5-Ω resistor, and a flashlight lamp. In which of the following circuit connections will the flashlight lamp be brightest?

Connect the lamp in parallel with both the battery and the 5-Ω resistor. Connect the lamp in parallel with both the battery and the 10-Ω resistor. Connect the lamp directly to the battery without using any resistor.

Ignoring the internal resistance of the battery, which of the following statements are correct when a battery has an electromotive force of 10 V?

Each coulomb of charge leaves the battery with 10 joules of energy.

Select all that apply Which of the following statements does NOT represent Ohm's law?

I/ΔV = constant I = ΔV × R ΔV/I = constant

Select all that apply Which statements are correct about the voltmeter?

It has high resistance. It is always connected in parallel. It measures electrical voltage.

Select all that apply Which of the following statements are correct regarding Ohm's law?

Ohm's law shows that the voltage drop across a conducting wire is directly proportional to its resistance. Ohm's law shows that the current in a conducting wire is inversely proportional to its resistance.

Select all that apply Which of the following would be called an electrical current moving to the left?

Positive charges moving to the left Negative charges moving to the right

Select all that apply What does a battery do with the energy it gains?

Separates the positive and negative charges. Does work to increase the electric potential energy.

Select all that apply A 120 Ω resistor and a 34 Ω resistor are connected in series with a power supply. Which of the following statements are correct?

The current is the same through both resistors. The voltage drop across the 120 Ω resistor is larger than the drop across the 34 Ω resistor.

Which is true about the current flowing through a series circuit?

The current provided by the power source flows equally through each of the resistors in the circuit.

Select all that apply Which of the following is true about the voltage in a series circuit?

The voltage will decrease across each resistor. The sum of the individual voltage changes will be equal to the total voltage applied across the series circuit. The voltage changes across the resistors will follow Ohm's law.

When studying electricity, the word "circuit" could refer to

a battery, a wire (or wires), and a light bulb connected in a closed path.

Electric current is defined as the amount of______ flowing per unit________.

charge time

When a closed loop is formed with a source of electrical power (such as a battery) such that an electric current can flow, we call this an electrical ___________________

circuit

In Ohm's law (ΔV = I × R), I represents the_______in units of______while R represents the________in units of________.

current ampere resistance ohm

An ammeter is a piece of equipment used to measure electrical_______while a voltmeter is a piece of equipment used to measure electrical_________

current voltage

Select all that apply An ampere is

equal to one coulomb/second. a unit of electric current.

Two identical resistors are connected in series in a closed circuit with a battery. The current in the second resistor is

equal to the current in the first resistor.

True or false: The direction of the conventional electric current is opposite to the direction of motion of the positive charge carriers.

false

Select all that apply The electric current is

inversely proportional to the time it takes charges to pass in a fixed time. directly proportional to the amount of charge passing in a fixed time. directed from positive to negative. measured in amperes.

Select all that apply You have an electricity source, some wire, and a light bulb. If you add a toaster to the circuit in series with the light bulb,

less current flows in the circuit. the light bulb becomes dimmer.

n electrical circuits, the voltmeter is always connected in___________hile the ammeter is always connected in__________

parallel series

You have a circuit made out of a battery, some wire, and a light bulb. If you add an additional bulb to the circuit in series with the first bulb,

the current will decrease.

Select all that apply The electromotive force is

the increase in potential energy per unit charge. an electric potential difference.

The increase in electric potential energy due to the separation of the positive and negative charges produces a_______difference between the two terminals of the battery.

voltage