Charges placed on a conductor ____________.AnswersA.

spread out over the surface of the conductor

B.

stay where they are placed

C.

gather in the center of the conductor

D.

vanish after a few moments

Question2.If the positive charge of an atom's nucleus exactly balances the negative charge of the surrounding electrons, the atom is __________.AnswersA.

static

B.

electrified

C.

neutral

D.

positively-charged

Question3.If a positively-charged glass rod is suspended so that it turns easily, and another positively-charged glass rod is brought close to it, the two rods will __________.AnswersA.

not react

B.

fuse

C.

attract each other

D.

repel each other

Question4.

The best explanation for why the phenomenon in the figure below occurs is

AnswersA.

the Styrofoam peanuts are gravitationally attracted to the cat's fur.

B.

the opposite electrical charges on the cat's fur and Styrofoam peanuts are attracted to each other.

C.

the Styrofoam peanuts are magnetically attracted to the cat's fur.

D.

the same electrical charges on the cat's fur and Styrofoam peanuts are attracted to each other.

Question5.

If a charge were added to the figure below between the two charges already there, what direction would the net force on it be?

AnswersA.

To the right, if charge is positive, to the left if it's negative.

B.

To the right, regardless of its sign.

C.

To the left, if charge is positive, to the right if it's negative.

D.

This cannot be determined without knowing more about the location of the charge.

Question6.Why is copper a good conductor?AnswersA.

Its protons and electrons move readily.

B.

Its electrons move readily.

C.

It always has a negative charge.

D.

It can be insulated.

Question7.

In the figure below, if the charge on the rod were positive, what effect, if any, would this have on the final result?

AnswersA.

The left sphere would still be positive and the right sphere would still be negative, but there would be more total charge on each.

B.

It would have no effect.

C.

The left sphere would be negatively charged and the right sphere would be positively charged, with the same amount of charge as in the original picture c.

D.

The left sphere would still be positive and the right sphere would still be negative, but there would be less total charge on each.

Question8.Charging by induction occurs when __________.AnswersA.

charge separation is used to charge an object without touching it

B.

electric charge causes the leaves of an electroscope to spread apart

C.

a neutral body is charged by touching it with a charged body

D.

a negatively-charged rod is touched to the knob of an electroscope

Question9.If you increase the distance between two charges, what happens to the force?AnswersA.

It stays the same.

B.

It vanishes.

C.

It increases.

D.

It decreases.

Question10.The magnitude of the charge of an electron is called the __________.AnswersA.

negative charge

B.

elementary charge

C.

secondary charge

D.

frequency

Question11.

How far apart are two electrons if they exert a force of repulsion of 2.5 N on each other? (K= 9.0 10⁹Nm²/C²andq_A=q_B)

AnswersA.

9.6 10¹⁵m

B.

1.6 10¹⁹m

C.

9.6 10¹⁵m

D.

1.5 10¹⁴m

Question12.An electron's charge is ________ in magnitude and _________ in sign from a proton's charge.AnswersA.

equal; same

B.

unequal; same

C.

equal; opposite

D.

unequal; opposite

Question13.Lines drawn to represent an electric field extend __________ a positive charge and __________ a negative charge.AnswersA.

away from, toward

B.

toward, toward

C.

toward, away from

D.

away from, away from

Question14.According to Coulomb's law, the force on a test charge is __________ the test charge.AnswersA.

greater than

B.

equal to

C.

less than

D.

proportional to

Question15.What is the magnitude of the electric field at a position that is 20.0 cm from a 8.0 10⁷C point charge? (K= 9.0 10⁹Nm²/C²)AnswersA.

3.6 10²N/C

B.

1.8 10¹N/C

C.

1.8 10⁵N/C

D.

3.6 10²N/C

Question16.What is the magnitude of the electric field at a distance twice as far from the point charge in question 15?AnswersA.

4.5 10⁴N/C

B.

9.0 10³N/C

C.

4.5 N/C

D.

9.0 10¹N/C

Question17.The __________ is a vector quantity that relates the force on a test charge to the size of the charge.AnswersA.

electric field

B.

equipotential

C.

potential

D.

capacitor

Question18.A negative charge of 1.5 10⁷C experiences a force of 0.030 N to the right in an electric field. What is the magnitude and direction of the field?AnswersA.

4.5 10⁷N/C directed to the right

B.

2.0 10⁵N/C directed to the right

C.

4.5 10⁹N/C directed to the left

D.

2.0 10⁵N/C directed to the left

Question19.

In the set-up of the figure below, if a drop is falling at a constant velocity, then __________.

AnswersA.

the lower plate must be negatively charged

B.

the upper plate must be negatively charged

C.

the gravitational force on the drop must be equal to the electric force on the drop

D.

the gravitational force on the drop must be less than the electric force on the drop

Question20.Two parallel plates are given opposite charges. A voltmeter measures the electric potential difference to be 47.0 V. The plates are 5.0 cm apart. What is the magnitude of the electric field between them?AnswersA.

1.1 10³N/C

B.

2.4 10²N/C

C.

9.4 10²N/C

D.

9.4 10³N/C

Question21.Both a 1.2-F and a 5.5-F capacitor are connected across an 11-V electric potential difference. Which capacitor has the greater charge and what is it?AnswersA.

5.5-F; 1.3 10⁵C

B.

1.2-F; 6.1 10⁵C

C.

1.2-F; 1.3 10⁵C

D.

5.5-F; 6.1 10⁵C

Question22.The electric field intensity between two large, charged, parallel metal plates is 6500 N/C. The plates are 12 cm apart. What is the electric potential difference between them?AnswersA.

7.8 10²V

B.

7.8 10²V

C.

7.8 10⁴V

D.

7.8 10⁵V

Question23.Electric potential difference is measured in __________.AnswersA.

joules per coulomb

B.

coulombs per joule

C.

newtons per coulomb

D.

volts per coulomb

Question24.When the electric potential difference between two positions in an electric field is zero, the positions are __________.AnswersA.

polar

B.

in equilibrium

C.

close together

D.

at equipotential

Question25.What work is done when 3.5 C is moved through an electric potential difference of 4.5 V?AnswersA.

1.6 10¹J/C

B.

1.6 10¹J

C.

1.6 10¹J

D.

7.8 10¹J

Question26.

If the combined resistance of the potentiometer and motor in the figure below is 250 , what is the current through the circuit?

AnswersA.

48 mA

B.

21 A

C.

120 A

D.

3000 A

Question27.

For the circuit arrangement shown in the figure below, if the battery voltage is increased to 9.0 V and the ammeter reads 0.60 A. What is the new circuit's resistance?

AnswersA.

30

B.

15

C.

5.4

D.

0.06

Questions 28-37

Use the diagram and information to answer questions 28-30.

Question28.If the ammeter in the figure above were moved to the left of the lightbulb, what would it read?AnswersA.

1 A

B.

0 A

C.

4 A

D.

3 A

Question29.If the resistance of the lightbulb in the figure above were changed to 6 , what would the ammeter read?AnswersA.

4 A

B.

2 A

C.

6 A

D.

8 A

Question30.In the figure above, if the battery voltage were changed to 9 V, what would the ammeter reading be?AnswersA.

3 A

B.

1 A

C.

2 A

D.

4 A

Question31.What is the effect on the current in a simple circuit if both the voltage and the resistance are reduced by half?AnswersA.

divided by 2

B.

multiplied by 2

C.

multiplied by 4

D.

no change

Question32.A 12.0 V battery delivers a 1.20 A current to an electric motor that is connected across terminals. What power is consumed by the motor?AnswersA.

14.4 W

B.

14.4 J

C.

10.0 J

D.

10.0 W

Question33.What is a superconductor?AnswersA.

a magnet

B.

a powerful battery

C.

a material with zero resistance

D.

a material with a very high resistance

Question34.A 75.0 W lightbulb is 25.0% efficient. How many joules of thermal energy does the lightbulb produce each minute?AnswersA.

1130 J

B.

563 J

C.

4500 J

D.

3380 J

Question35.A kilowatt-hour is equivalent to __________.AnswersA.

1.0 10³J

B.

3.6 10⁶J

C.

3.6 10⁶J/s

D.

1.0 10³J/s

Question36.Thermal energy is given by __________.AnswersA.

E=Pt

B.

E=IR

C.

E=P²t

D.

E=I²R

Question37.If a flashlight with a voltage of 4.5 V and a current of 0.50 A is on for 3.0 min, how much electrical energy is delivered to the bulb?AnswersA.

6.9 J

B.

14 J

C.

2.0 10²J

D.

4.1 10²J

Questions 38-50

Use the diagram and information to answer questions 38 and 39.

Question38.Which pair of options below would result in a greater reading onV_Bin the figure above?AnswersA.

increase the battery voltage or decreaseR_B

B.

decrease the battery voltage or decreaseR_B

C.

increase the battery voltage or decreaseR_A

D.

decrease the battery voltage or decreaseR_A

Question39.Which pair of options below would result in a lower reading onV_Bin the figure above?AnswersA.

increase the battery voltage or decreaseR_B

B.

decrease the battery voltage or decreaseR_B

C.

decrease the battery voltage or decreaseR_A

D.

decrease the battery voltage or increaseR_A

Question40.If you have a 90 V power source with a 30- and 60- resistor in series, what is the voltage drop over the 60- resistor?AnswersA.

90 V

B.

60 V

C.

30 V

D.

2 V

Question41.Two 240.0- resistors are connected in parallel and placed across a 12.0-V battery. What is the current in each branch of the circuit?AnswersA.

0.0125 A

B.

0.100 A

C.

0.0500 A

D.

0.0250 A

Question42.

In the figure below, if a third resistor were added to the circuit somewhere between resistors A and B, how would the reading on the bottom ammeter change, if at all?

AnswersA.

This cannot be determined without knowing the value of the new resistor.

B.

It would decrease.

C.

It would increase.

D.

It wouldn't change.

Question43.What happens to lights in series if one goes out?AnswersA.

they all go out

B.

every other one goes out

C.

they flicker

D.

they stay lit

Question44.In the river model for an electric circuit, the amount of water flowing through the river each second is the __________.AnswersA.

path

B.

voltage

C.

power

D.

current

Question45.What causes a fuse to blow?AnswersA.

too low a resistance

B.

too high a voltage

C.

too much resistance

D.

too high a current

Question46.Voltmeters must have __________.AnswersA.

very low resistance

B.

very high currents

C.

very high resistance

D.

very high voltage

Question47.Why must an ammeter have an extremely low resistance?AnswersA.

High resistance will change the current in the circuit you want to measure.

B.

High resistance changes the voltage reading.

C.

High resistance ensures there are fewer ohms.

D.

High resistance reduces risk of fire.

Question48.Electrical wiring in homes uses __________ circuits.AnswersA.

overloaded

B.

parallel

C.

voltage

D.

series

Question49.What happens when an electric switch is turned off?AnswersA.

There is a short circuit.

B.

A circuit breaker turns off.

C.

The circuit is broken.

D.

The circuit becomes a series circuit.

Question50.How does a ground-fault interrupter work?AnswersA.

It detects small differences in current caused by an extra current path and opens the circuit.

B.

It detects small differences in temperatures and opens the circuit.

C.

It detects small differences in voltage caused by an extra voltage path and opens the circuit.

D.

It detects small differences in resistance and opens the circuit.

I just need the letter answers no explanation