AnswersLHS Physical ScienceUnit Test

Unit Test — Unit test Answers

25 verified answers1 views
1
Free Preview

Ohm’s law describes the relationship between which quantities?

A
voltage, resistance, and ohms
B
resistance, current, and amperes
C
current, voltage, and resistance
D
amperes, ohms, and current
2
Free Preview

How are the magnetic field lines near the south pole of a magnet affected when a second south pole is brought near it?

A
The field lines combine with the lines around the second south pole.
B
The field lines overlap with the lines from the second south pole.
C
The field lines bend toward the second south pole.
D
The field lines bend away from the second south pole.
3

A bar magnet is cut in half, as shown. Which shows the pieces after the magnet is cut?

Question illustration
A
2 pieces of broken magnet with a jagged edge on the inside side of each piece. On the left a piece labeled N S from left and on the right a piece labeled N S from left.
B
2 pieces of broken magnet with a jagged edge on the inside side of each piece. On the left a piece labeled N S from left and on the right a piece labeled S N from left.
C
2 pieces of broken magnet with a jagged edge on the inside side of each piece. On the left a piece labeled N and on the right a piece labeled S.
D
2 pieces of broken magnet with a jagged edge on the inside side of each piece. On the left a piece labeled S and on the right a piece labeled N.
4

Tisa makes a diagram to organize her notes about charging objects.

Question illustration
A
Electrons move between objects.
B
The objects do not touch.
C
The objects develop opposite charges.
D
The objects have the same charge.
5

Mateo makes a table of the symbols that represent the parts of an electric circuit.

Question illustration
A
Uses electrical energy
B
Provides electrical energy
C
Measures electric current
D
Controls electric current
6

Frances drew a diagram to show electromagnetic induction.

Question illustration
A
Current
B
Magnetic field
C
Solenoid
D
Force on wire
7

In a movie, a character cuts a wire, which stops the countdown timer of a bomb. What does cutting the wire do to the circuit?

A
It opens the circuit so that electric charges do not flow to the timer.
B
It closes the circuit so that electric charges do not flow to the timer.
C
It opens the circuit so that electric charges flow to the timer.
D
It closes the circuit so that electric charges flow to the timer.
8

What is the resistance of a clock if it has a current of 0.30 A and runs on a 9.0-V battery?

A
0.033
B
2.7
C
9.3
D
30
9

Nina is working with electricity and shortens the wires through which the current is flowing. What is Nina most likely trying to accomplish?

A
convert electric energy to heat
B
convert electric energy to light
C
increase resistance
D
decrease resistance
10

How does increasing the distance between charged objects affect the electric force between them?

A
The electric force increases because the distance has an indirect relationship to the force.
B
The electric force increases because the distance has a direct relationship to the force.
C
The electric force decreases because the distance has an indirect relationship to the force.
D
The electric force decreases because the distance has a direct relationship to the force.
11

What is required for an electric charge to flow through a wire?

A
zero resistance in the wire
B
a balance of electric potential
C
high resistance in the wire
D
a difference in electric potential
12

Georgia moves an unattached piece of wire back and forth over a magnet. Which best explains what will happen?

A
A current will be induced because the wire moves through a magnetic field.
B
A current will not be induced because the wire moves through a magnetic field.
C
A current will be induced because the wire is not part of a closed circuit.
D
A current will not be induced because the wire is not part of a closed circuit.
13

Cora, an electrician, wraps a copper wire with a thick plastic coating. What is she most likely trying to do?

A
keep the electric potential of the wire balanced
B
decrease the wire’s resistance
C
increase the voltage produced by the wire
D
keep a current from passing out of the wire
14

An object that is made of which material is likely to be attracted to a magnet?

A
nitrogen
B
nickel
C
paper
D
plastic
15

How are the current and resistance related when the voltage of a circuit is constant?

A
The current doubles when the resistance doubles because they are directly proportional.
B
The current doubles when the resistance doubles because they are inversely proportional.
C
The current is cut in half when the resistance doubles because they are directly proportional.
D
The current is cut in half when the resistance doubles because they are inversely proportional.
16

Potential difference is measured in which units?

A
volts
B
amps
C
currents
D
watts
17

Which device manages the flow of current in an electric circuit?

A
the wire
B
the switch
C
the battery
D
the light bulb
18

Which statement correctly describes Earth’s magnetic field?

A
A compass can lead a hiker to the geographic North Pole.
B
The magnetic pole near the South Pole is a north pole.
C
Compasses point toward a magnetic pole that is a north pole.
D
Field lines circle Earth from east to west.
19

Aretha measures a circuit at 110 V and 240 . Using Ohm’s law, what can she calculate for the circuit?

Question illustration
A
voltage
B
ohms
C
resistance
D
current
20

What is an advantage of series circuits?

A
Adding more batteries will increase the current.
B
There is more than one path for charges to flow.
C
If one bulb goes out, the other bulbs still shine.
D
Light bulbs get dimmer as more bulbs are added.

Did you find these answers helpful?

More from this Course

Quiz
25 verified answers

Unit Test

Quiz
25 verified answers

Unit Test

Quiz
25 verified answers

Unit Test