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?

Question

options:

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

Answer 1

When a negatively charged rod touches a neutral metal sphere, the excess negative charge (electrons) from the rod will move onto the neutral sphere. This transfer occurs because like charges repel, and the negatively charged rod will push electrons away from itself.

Since the sphere was initially neutral, it can accept the additional electrons without becoming negatively charged immediately; however, after the contact, the sphere will have a negative charge, as it now contains excess electrons.

So, the correct option is:

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

Answer 2

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?

options:

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 3

To determine which magnet has the most magnetic energy, Kennedy should focus on a method that evaluates the strength of the magnets' magnetic fields and their ability to interact with other materials.

Among the provided options, the best way to assess the magnetic strength (and, indirectly, the magnetic energy) of the two magnets would be to:

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

This method will effectively indicate the strength of the magnetic field generated by each magnet, as a stronger magnet will be able to attract a metal object from a greater distance. The other options do not effectively measure magnetic energy.

Answer 4

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?

options:

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.

Answer 5

To maximize the strength of the electromagnet that Diego is creating, he should aim to increase the number of coils of wire wrapped around the nail and ensure that these coils are close together. More coils produce a stronger magnetic field when current flows through the wire.

Therefore, the best option for Diego to ensure he picks up the most paper clips is:

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

This will enhance the magnet's strength and allow it to pick up more paper clips effectively.