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8th grade · Science · Unit 5 of 10

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.

Minnesota K-12 Academic Standards benchmark: 8P.1.2.1.3; 8P.3.1.1.3; 8P.4.1.1.1 · electric, magnetic and gravitational fields between objects that don't touch

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 Minnesota

In the Minnesota K-12 Academic Standards, this is unit 5 of 10 in 8th grade Science, after Circuits & Static and before Newton's Laws.

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: Minnesota Department of Education (MDE)

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

    A field is a region where…

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

  2. Question 2

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

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

  3. Question 3

    Iron filings around a bar magnet show…

    • gravity
    • electric current
    • magnetic field lines
    • heat

  4. Question 4

    Gravity between two objects is stronger when they are…

    • less massive and farther
    • the same color
    • colder
    • more massive and closer

  5. Question 5

    Adding more coils to an electromagnet makes it…

    • colder
    • stronger
    • lighter
    • weaker

  6. Question 6

    Which object has the strongest gravitational pull on you right now?

    • Your desk
    • The moon
    • The sun
    • Earth

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