Unit 7 Lesson 3: Noncontact Forces

Multiple Choice

Which of the following is an example of a non-contact force?

• Gravity pulling the Earth and Sun together

• Pushing a box across the floor

• Friction between shoes and the ground

• Tension in a stretched rope

Multiple Choice

Which two variables directly affect the strength of gravitational attraction between objects?

• Mass and distance

• Volume and density

• Temperature and pressure

• Speed and direction

Multiple Choice

On which celestial body would a person with a mass of 50 kg weigh the least, and why?

• Earth, because it has the strongest gravity

• Mars, because it has less gravity than Earth but more than the Moon

• Moon, because it has the weakest gravity

• All would weigh the same because mass doesn't change

Multiple Choice

What is the term for an unbalanced positive or negative charge on an object?

• Static charge

• Electric field

• Current

• Voltage

Multiple Choice

Which of the following best describes an electric field?

• A region where magnetic forces act on objects

• A region surrounding a charged object where electric forces act on other charged objects

• A region where objects must touch to interact

• A region with no interaction between objects

Multiple Choice

How does the distance between two charged objects affect the strength of the electric field between them?

• The strength increases as the distance increases

• The strength decreases as the distance decreases

• The strength increases as the distance decreases

• Distance does not affect the electric field

Multiple Select

Which of the following statements about magnetic force is/are correct?

• Magnetic force is strongest at the magnetic poles

• Magnetic force requires contact between magnets

• The closer the magnets, the stronger the force

• A magnetic field is produced even if magnets do not touch

Multiple Choice

What happens to the strength of the magnetic field around a wire as the amount of electric current in the wire increases?

• It decreases

• It remains the same

• It increases

• It disappears

Multiple Choice

What are some examples of non-contact forces shown in the images?

• Magnetic force, gravitational force, electrostatic force

• Friction, air resistance, tension

• Normal force, applied force, spring force

• Buoyant force, compressive force, torsion