8th grade · Science · Unit 4 of 8
Fields & Forces at a Distance
Gravity, magnetism and electric forces.
What your child practices
Practices forces that act without touching: what affects electric and magnetic force strength, why gravity is always attractive and depends on mass, and how fields store energy.
California Content Standards learning standard: MS-PS2-3; MS-PS2-4; MS-PS2-5 · electric, magnetic and gravitational forces that act at a distance
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
An electromagnet is made by…
- freezing a magnet
- heating a rock
- rubbing a balloon
- running current through a coil of wire
running current through a coil of wire
Hint: Electricity makes magnetism.
Question 2
Which keeps the planets in orbit around the sun?
- Friction
- Magnetism
- Gravity
- Static electricity
Gravity
Hint: The sun's pull.
Question 3
A field is a region where…
- it's always hot
- nothing happens
- only light exists
- an object feels a force
an object feels a force
Hint: Fields act at a distance.
Question 4
Adding more coils to an electromagnet makes it…
- lighter
- weaker
- colder
- stronger
stronger
Hint: More loops, stronger field.
Question 5
Which force can act without touching?
- Tension
- Friction
- Magnetism
- Air resistance
Magnetism
Hint: A magnet pulls a paper clip from a distance.
Question 6
Which change makes the electric force between two charges stronger?
- Paint them
- Make them neutral
- Increase the charges
- Increase the distance
Increase the charges
Hint: More charge, more force.