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8th grade · Science · Unit 4 of 7

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.

Alaska content standards learning standard: MS-PS2-3; MS-PS2-4; MS-PS2-5 · electric, magnetic and gravitational forces that act at a distance

How we explain it

Children can open this short lesson before they practice.

  1. Some forces act without touching: gravity, magnetism and electric force.
  2. Gravity always attracts and is stronger with more mass. Electric and magnetic forces can push or pull.
  3. More current makes an electromagnet stronger; closer objects feel stronger forces.

Example: A rubbed balloon sticks to a wall. Which force is this? Rubbing moves electrons onto the balloon. Charged objects attract. Answer: static electric force

Fields & Forces at a Distance in Alaska

In the Alaska content standards, this is unit 4 of 7 in 8th grade Science, after Kinetic & Potential Energy and before Genes & Heredity.

Gradelings describes a child's practice on this unit as Beginning, Approaching, Meeting or Exceeding (Four practice steps). That reflects practice, not a report-card mark: the teacher decides the mark.

Source: Alaska Department of Education and Early Development

Sample questions

A taste of this unit. In the app, questions change every time and get easier or harder to match your child.

  1. Question 1

    Adding more coils to an electromagnet makes it…

    • weaker
    • colder
    • lighter
    • stronger

  2. Question 2

    Increasing current in an electromagnet makes it…

    • reversed in mass
    • stronger
    • weaker
    • unchanged

  3. Question 3

    Like electric charges…

    • repel
    • disappear
    • become neutral always
    • attract

  4. Question 4

    A field is a region where…

    • nothing happens
    • it's always hot
    • an object feels a force
    • only light exists

  5. Question 5

    As two magnets move farther apart, the force between them…

    • reverses
    • gets stronger
    • stays the same
    • gets weaker

  6. Question 6

    Which change makes the electric force between two charges stronger?

    • Paint them
    • Increase the charges
    • Make them neutral
    • Increase the distance

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