Magnetism and Electricity

1.

4 points

A conductor differs from an insulator in that a conductor

has less resistance for current to travel

has less voltage that travels

has more resistance for current to travel

has more voltage that travels

2.

4 points

During a physics lab, a plastic strip was rubbed with cotton and the charges separated. This occurred due to ...

charge by polarization

charge by induction

charge by friction

charge by contact

3.

4 points

The symbol used to represent resistance in a schematic diagram is

two straight lines.

one straight line.

a zigzag line.

a single line that is broken

4.

4 points

Protons and electrons

do not interact.

not enough information

repel each other

attract each other.

5.

4 points

What is the resistance if voltage is 5.0 V and current is 1.32 A?

0.264 A

0.264 Ω

3.78 A

3.78 Ω

6.

4 points

What is the difference between charge by induction and charge by polarization

charge by induction is with conductors and charge by polarization is with insulators

charge by induction is with the objects do not touch and charge by polarization is when the object touch

charge by induction is when the objects touch and charge by polarization is when the object do not touch

charge by induction is with insulators and charge by polarization is with conductors

7.

4 points

A closed circuit is a circuit in which charge

charge can flow

charge flows through insulators

charge cannot flow

not enough information

8.

4 points

A bird can sit on a power line with two feet because

there is no change in voltage between the birds two feet

no current actually flows in power lines

there current flows through the bird from high to low voltage

the bird is an insulator so current cannot ever flow through it

9.

4 points

Which law evaluates the relationship between voltage, current and resistance is...

law of conservation of charges

Ohm's law

Coulomb's law

not enough information

10.

4 points

The q in Coulomb's law equation stands for the _____.

charge of a charged object

# of excess electrons on the object

mass of a charged object

the current of a charged object

11.

4 points

A charge of 0.15 C moves vertically in magnetic field of 0.18 T that is oriented horizontally. What speed must the charge have to experience a force of 12 N?

14.4 m/s

444 m/s

0.324 m/s

0.00225 m/s

12.

4 points

What are regions of atoms that magnetically aligned?

magnetic domains

magnetic charges

magnetic fields

magnetic forces

13.

4 points

The SI unit of charge is the

ohm (Ω)

coulomb (C)

tesla (T)

ampere (A)

14.

4 points

Rubber is put around wires to protect humans from the heat generated by current flowing through the wire. Rubber is used because it is a(n) _____.

inducer

voltage

insulator

conductor

15.

4 points

Which law identifies the force of attraction between two charges based upon the inverse square of the distance between the charges?

Law of conservation of charges

law of polarization

Coulomb's law

Ohm's law

16.

4 points

Two charges separated by a distance of 1 meter exert a 20-N force on each other. If the charges are pulled to a 2 meter separation distance, the force on each charge will be

0 N

10 N

40 N

5 N

17.

4 points

A positive charge of 1.21 C moves at 2547 m/s and enters a magnetic field. If it experiences a force of 12 N, what is the magnetic field strength?

25259.5 B

0.0039 B

0.0039 T

25259.5 T

18.

4 points

Marie blows a fuse in her bedroom. All of the lights and appliances go out in her room. When she checks on the rest of the house, she realizes that the power is on in all of the other rooms. This is because the house is wired in ____.

induction

parallel

polarization

series

19.

4 points

Magnets can be made by

placing a piece of iron near a strong electromagnet.

placing a piece of iron in a strong magnetic field.

stroking material containing iron with a magnet.

all of the above

20.

4 points

A current is said to exist whenever _____.

a wire is charged

electric charges move in a loop

electric charges are unbalanced

a battery is present

21.

4 points

An example of a voltage source is

motor

wire

battery

light bulb

22.

4 points

What is the symbol for magnetic field?

T

B

I

q

23.

4 points

Magnetic field strength is

strongest close to a magnet.

strongest far from a magnet.

constant everywhere around a magnet.

Not enough information

24.

4 points

In order for current to flow in a circuit, there must be

two light bulbs in series.

a switch that is open.

voltage and a complete closed path.

two light bulbs in parallel.

25.

4 points

During a physics lab, a plastic strip was rubbed with cotton and became positively charged. When the plastic strip was touched to a piece of aluminum foil, the foil moved toward the plastic strip. The attraction of the plastic strip and foil is due to...

charge by contact

charge by polarization

charge by induction

charge by friction