A teacher places a metal can on top of an insulating foam cup and touches the side of the foam cup with a negatively charged rod. The setup is shown in the picture below.

Question

What will happen to the negatively charged electrons when the rod touches the foam cup?

(1 point)
Responses

The electrons will transfer to the foam cup and will remain in a concentrated, positively charged area on the cup where the rod was placed.

The electrons will transfer to the foam cup and will remain in a concentrated, negatively charged area on the cup where the rod was placed.
The electrons will transfer to the foam cup and will remain in a concentrated, negatively charged area on the cup where the rod was placed.

The electrons will transfer from the foam cup to the metal can, causing both cup and can to have a positive charge.
The electrons will transfer from the foam cup to the metal can, causing both cup and can to have a positive charge.

The electrons will transfer from the foam cup to the metal can, causing both the cup and can to have a negative charge.
The electrons will transfer from the foam cup to the metal can, causing both the cup and can to have a negative charge.
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Answer 1

When a negatively charged rod touches the insulating foam cup, the electrons from the rod will be transferred to the foam cup. Since the foam cup is an insulator, the electrons will remain in the cup where the rod was placed, creating a concentrated area of negative charge.

Therefore, the correct response is:

The electrons will transfer to the foam cup and will remain in a concentrated, negatively charged area on the cup where the rod was placed.

Answer 2

A balloon and a section of a wall both have neutral charges, as shown below.




A student rubs his hair on the balloon, giving it a negative charge. How will the charges be arranged in the wall when it is placed near the negatively changed balloon?

(1 point)
Responses

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Answer 3

When the negatively charged balloon is brought near the neutral wall, it will induce a separation of charges within the wall. The electrons in the wall will be repelled by the negatively charged balloon, causing them to move away from the side of the wall that is closer to the balloon. This results in a positive charge on the side of the wall nearest to the balloon (as the electrons move away), while the side of the wall farther from the balloon remains neutral.

Thus, when the negatively charged balloon is placed near the wall, the charges will be arranged as follows:

• The side of the wall closest to the balloon will become positively charged (due to the deficiency of electrons).
• The side of the wall farthest from the balloon will remain neutral.

So, the overall effect is that the wall will become polarized with a positive charge near the negatively charged balloon.

Answer 4

Calvin touches a negatively charged rod to a neutral metal sphere located on an insulated stand. What will happen to the electrons when the negatively charged rod touches the metal sphere?(1 point)
Responses

electrons will move from the sphere to the rod
electrons will move from the sphere to the rod

electrons will move from the rod to the sphere and spread out
electrons will move from the rod to the sphere and spread out

electrons will move from the rod to the sphere but stay close together
electrons will move from the rod to the sphere but stay close together

electrons will move from the sphere to the rod and stay close together
electrons will move from the sphere to the rod and stay close together

Answer 5

When the negatively charged rod touches the neutral metal sphere, electrons from the rod will move to the sphere. This happens because the sphere is neutral, and when it comes into contact with the negatively charged rod, the excess electrons from the rod will transfer to the sphere.

Once the electrons move to the sphere, they will spread out evenly across its surface, due to the nature of conductors allowing charges to distribute uniformly.

Therefore, the correct response is:

electrons will move from the rod to the sphere and spread out.

Answer 6

The drawing shows a person holding two negatively charged balloons.



What is most likely to happen if one of the balloons is brought close to a positively charged piece of wool?

(1 point)
Responses

The magnitude of the electrostatic force between the balloon and the wool will increase, and they will repel each other.
The magnitude of the electrostatic force between the balloon and the wool will increase, and they will repel each other.

The magnitude of the electrostatic force between the balloon and the wool will increase, and they will attract each other.
The magnitude of the electrostatic force between the balloon and the wool will increase, and they will attract each other.

The magnitude of the electrostatic force between the balloon and the wool will decrease, and they will repel each other.
The magnitude of the electrostatic force between the balloon and the wool will decrease, and they will repel each other.

The magnitude of the electrostatic force between the balloon and the wool will decrease, and they will attract each other.
The magnitude of the electrostatic force between the balloon and the wool will decrease, and they will attract each other.
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Answer 7

When one of the negatively charged balloons is brought close to a positively charged piece of wool, the balloon and wool will experience an attractive electrostatic force. This is due to the fact that opposite charges attract each other.

As the balloon approaches the wool, the magnitude of the electrostatic force between them will increase because they are getting closer together.

Therefore, the correct response is:

The magnitude of the electrostatic force between the balloon and the wool will increase, and they will attract each other.

Answer 8

Kennedy has two magnets. She would like to determine how much magnetic energy is stored in each one. What would be the best way for her to determine which magnet has the most magnetic energy?(1 point)
Responses

Attach wires to the ends of each magnet and measure the flow of electricity going through the wires.
Attach wires to the ends of each magnet and measure the flow of electricity going through the wires.

Put each magnet into a beaker of water to see how much water it displaces.
Put each magnet into a beaker of water to see how much water it displaces.

Measure how close each magnet can get to a metal object before picking it up.
Measure how close each magnet can get to a metal object before picking it up.

Record the weight of each magnet by measuring it on a balance scale.

Answer 9

To determine which magnet has the most magnetic energy, the best approach would be to measure how close each magnet can get to a metal object before picking it up. This method will give a practical indication of the strength of the magnetic field produced by each magnet.

Therefore, the correct response is:

Measure how close each magnet can get to a metal object before picking it up.

Answer 10

Read the passage about Diego’s experiment:

Diego wants to make an electromagnet for the science fair. He only has a nail, copper wire, and a 9-volt battery. His experiment is to make a magnet strong enough to pick up paper clips. He wants to prove that his magnet can pick up the most clips.


What can Diego do to his magnet to make sure he picks up the most paper clips?

(1 point)
Responses

Diego can wrap a few coils of the wire, far apart, around the nail.
Diego can wrap a few coils of the wire, far apart, around the nail.

Diego can wrap many coils of the wire, far apart, around the nail.
Diego can wrap many coils of the wire, far apart, around the nail.

Diego can wrap a few coils of the wire, close together, around the nail.
Diego can wrap a few coils of the wire, close together, around the nail.

Diego can wrap many coils of the wire, close together, around the nail.
Diego can wrap many coils of the wire, close together, around the nail.
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Answer 11

To maximize the strength of the electromagnet and ensure that it can pick up the most paper clips, Diego should wrap many coils of the wire tightly (close together) around the nail. More coils of wire create a stronger magnetic field when an electric current flows through them.

Therefore, the correct response is:

Diego can wrap many coils of the wire, close together, around the nail.