Unit 2 Lessons 1 and 2 Electricity and Magnetism

The distance between a positively charged object and a negatively charged object increases. If everything remains the constant, what happens to the electric force between the objects?

• The electric force decreases.

• The electric force increases.

• The electric force remains constant.

• There is not enough information to answer the question.

What happens when a balloon is rubbed on the hair, giving it a negative charge?

• Negative charges are moved from the balloon to the hair.

• Negative charges are moved from the hair to the balloon.

• Negative charges are added to the balloon, and the hair remains neutral.

• Positive charges are removed from the balloon, and the hair remains neutral.

The diagram shows two pairs of charged objects. Objects A and B are interacting with each other, and objects C and D are interacting with each other. Based on the diagrams, which statement is true?

• There are no electric forces because the charges in each pair of objects cancel.

• The electric force between A and B is smaller than the electric force between C and D.

• The electric force between A and B is greater than the electric force between C and D.

• The electric force between A and B is identical in magnitude to the electric force between C and D.

This image shows two circular objects. Each object has an electric charge, as shown. Which statement best describes the force that is exerted on the objects due to their electric charges?

• There is a force pushing both objects to the left.

• There is a force pushing both objects towards each other.

• There is a force pushing both objects away from each other.

• There is no force on the objects due to their electric charge.

During a lightning storm, the bottom of a cloud gains a strong negative electric charge. Which of these describes the charge at the top of a metal pole directly under the cloud?

• The top of the pole would have no charge.

• The top of the pole would have a positive charge.

• The top of the pole would have a negative charge.

• The charge of the pole would not be affected by the charge of the cloud.

When Amy walks across a carpet, her socks pick up many electric charges. Later in the day, these charges are no longer present on her socks. What most likely happened to the charges?

• The charges disappeared.

• The charges switched signs.

• The charges transferred to another object.

• The charges broke apart into smaller particles.

A repelling force occurs between two charged objects when the charges are of ________________.

• like signs

• unlike signs

• equal magnitude

• unequal magnitude

Tags

NGSS.MS-PS2-3

NGSS.MS-PS2-5

Why can some objects be magnetized by rubbing one pole of an existing magnet in one direction along the object?

• The motion of the existing magnet against the object aligns the magnetic domains of the object.

• The motion of the existing magnet against the object scrambles, or randomly distributes, the magnetic domains of the object.

• The motion of the existing magnet against the object generates an electric current that transforms the object into an electromagnet.

• The motion of the existing magnet against the object wears away the object's surface, exposing the naturally occurring magnets underneath.

A magician wants to use magnets to create a new illusion for her show. She plans to hide strong magnets in her shoes and inside a special rug on stage. When she tests the illusion, she finds that her shoes stick to the rug. What will happen if she flips the poles of the magnets in each of her shoes?

• Her shoes will float above the rug.

• Her shoes will still be stuck the rug.

• Her shoes will no longer be affected by the rug.

• Her shoes will stick to each other instead of the rug.

Tags

NGSS.MS-PS2-3

NGSS.MS-PS2-5

Which of these determines whether or not a material is magnetic?

• the density of the material.

• the weight of the material on Earth.

• the alignment of atoms in the material.

• the number of elements that make up the material.

Tags

NGSS.MS-PS2-3