Unit 6 Review Physical Science

A student rubs a balloon against a wool sweater and then places it near a piece of paper. The paper is attracted to the balloon and sticks to it. What is the best explanation for why this happens?

• Friction causes electrons to move from the paper to the balloon, creating a magnetic force.

• The balloon becomes positively charged, and the wool sweater becomes negatively charged, producing a gravitational pull on the paper.

• Friction causes electrons to move from the wool sweater to the balloon, creating an imbalance of static electrical charges.

• The wool sweater conducts electricity, allowing the balloon to create heat that attracts the paper.

The property of matter that affects the flow of electricity is called its—

• Chemical balance

• Durability

• Flammability

• Resistance

Which of the following terms easily allows the transfer of an electric current?

• Conductor

• Insulator

• Semiconductor

Fill in the blank: _______ does not easily allow the transfer of an electric current.

• A) Aluminum

• B) Copper

• C) Glass

• D) Rubber

• E) Silicon

Which of the following materials easily allows the transfer of an electric current?

• Glass

• Rubber

• Aluminum

• Silicon

In the experiment, which material caused the lightbulb to light up? Fill in the blank: The lightbulb lit up with the ______.

• A) Wooden popsicle stick

• B) Silver keys

• C) Gold ring

• D) Piece of paper

Which of the following are true about circuits in order for them to conduct electricity? Choose all that apply.

• Electrons need a complete pathway.

• Electrons travel from low to high potential.

• Electrons must receive energy from a source.

• Electrons transfer chemical energy to the surroundings.

A student is comparing two types of circuits: a simple electrical circuit that powers a light bulb and an electronic circuit used in a smartphone. Which of the following best explains an advantage of electronic circuits over electrical circuits?

• Electronic circuits generate more electricity than electrical circuits, making them more energy-efficient.

• Electronic circuits can process and store information, while electrical circuits are limited to providing power for basic tasks.

• Electronic circuits only use renewable energy, while electrical circuits rely on non-renewable energy sources.

• Electronic circuits are always smaller and cheaper to build than electrical circuits.

A student conducts an investigation using two bar magnets. The student places one magnet on a table and slowly moves the second magnet closer to it. The first magnet begins to move before the two magnets touch. What does this experiment provide evidence of?

• A gravitational field pulls the magnets together when they are close enough.

• The magnets create an electrical field that causes them to move toward each other.

• A magnetic field exists between the two magnets, allowing them to exert forces on each other without contact.

• The magnets repel each other because they are vibrating at the same frequency.

A student designs an experiment to investigate whether the strength of a magnetic field affects the distance a paperclip can be pulled toward a magnet. The student uses three different strength bar magnets (weak, medium, and strong) and measures the distance at which a paperclip starts moving. The student changes both the strength of the magnet and the size of the paperclip for each test. What should the student do to improve this experiment?

• Vary the number of magnets rather than the strength of the magnets.

• Change either the magnet size or the paperclip size, but not both.

• Measure how fast the paperclip moves, not the distance.

• Use a piece of paper as a control instead of a paperclip.