AnswersPhysical ScienceElectricity and Magnetism

Practice Test Answers

14 verified answers1 views
1
Free Preview

Which change will correct the error in Badri’s table?

A
changing “Direct” to “Indirect”
B
changing “Indirect” to “Direct”
C
changing “Distance” to “Amount of electric charge”
D
changing “Mass” to “Amount of electric charge”
2
Free Preview

Which best explains how Selena can correct her error?

A
She can change the arrows so they show current traveling in opposite directions on the sides of the loop.
B
She can change the magnetic poles so they are both on one side of the loop.
C
She can change the magnets so like poles are facing each other.
D
She can change the arrows so they show the magnetic field reversing direction between the magnets.
3

Two bar magnets are held close together. When they are released, they move toward one another. Which best describes the original placement of the magnets?

A
The magnets are placed end to end with the north pole of each pointing toward the other.
B
The magnets are placed side by side with the opposite poles of each magnet near the other.
C
The magnets are placed side by side with the like poles of each magnet near the other.
D
The magnets are placed end to end with the south pole of each pointing toward the other.
4

Which best compares a brush and a commutator in an electric motor?

A
Both rotate when the motor is on.
B
Both remain stationary when the motor is on.
C
Both carry electrical current from a power source.
D
Both have a permanent magnetic field.
5

Liang is working with an electrical circuit. She replaces a straight electrical wire with a coiled wire. What is Liang most likely trying to do?

A
decrease the current that flows through the wire when the circuit is active
B
increase the current that flows through the wire when the circuit is active
C
increase the strength of the magnetic field when current flows through the circuit
D
decrease the strength of the magnetic field when current flows through the circuit
6

Which unit is used to measure resistance?

A
charges
B
ohms
C
volts
D
amperes
7

A circuit has a current of 1 point 2 A If the voltage decreases to one-third of its original amount while the resistance remains constant, what will be the resulting current?

A
1 point 2 A
B
3 point 6 A
C
0 point 3 A
D
0 point 4 A
8

A circuit has a current of 2 A If the resistance in the circuit decreases to one-fourth of its original amount while the voltage remains constant, what will be the resulting current?

A
2 A
B
8 A
C
4 A
D
0 point 5 A
9

What does voltage describe?

A
how fast current can flow
B
how much a material resists electrical flow
C
how fast a material conducts electrical flow
D
how much current can flow
10

The north pole of a bar magnet is moved close to the north pole of a second bar magnet. What prediction best describes how the first magnet responds when it is released?

A
It will move toward the second magnet because like poles repel.
B
It will move away from the second magnet because like poles repel.
C
It will move toward the second magnet because like poles attract.
D
It will move away from the second magnet because like poles attract.
11

How many switches does the diagram show?

A
one
B
two
C
three
D
four
12

Based on the field lines, what are the charges of the objects?

A
A: negative B: positive
B
A: positive B: negative
C
A: positive B: positive
D
A: negative B: negative
13

Which best explains Horatio’s error?

A
The magnetic field does not continually spread outward from the wire.
B
The magnetic field is produced inside the wire, not outside of it.
C
Magnetism is not produced by electric currents unless the wire is coiled.
D
Magnetism is only produced when a metal bar is placed near the wire.
14

How would this change affect the electric circuit?

A
A switch is closed, so the circuit would be incomplete and broken and the lights in the circuit would not shine.
B
A switch is opened, so the circuit would be incomplete and broken and the lights in the circuit would not shine.
C
A switch is closed, so the circuit would be complete and unbroken and the lights in the circuit would shine.
D
A switch is opened, so the circuit would be complete and unbroken and the lights in the circuit would shine.

Did you find these answers helpful?

More from this Course

practice test
18 verified answers

Practice Test

practice test
15 verified answers

Practice Test

practice test
13 verified answers

Practice Test