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9th grade · Science · Unit 9 of 10

Energy & Magnetism

Conservation of energy, efficiency and electromagnets.

What your child practices

Practices the law of conservation of energy, potential and kinetic energy, efficiency, and the link between electric current and magnetic fields in electromagnets and generators.

Alaska content standards learning standard: HS-PS3-1; HS-PS2-5 · conservation of energy and magnetic fields from electric currents

How we explain it

Children can open this short lesson before they practice.

  1. Energy is never created or destroyed, only changed. Higher objects have more potential energy; faster ones more kinetic energy.
  2. Every magnet has two poles, north and south.
  3. Moving a coil of wire in a magnetic field makes electric current: that is how a generator works.

Example: Where does a roller coaster have the most potential energy? Potential energy depends on height. It is highest at the top. Answer: at its highest point

Energy & Magnetism in Alaska

In the Alaska content standards, this is unit 9 of 10 in 9th grade Science, after Evolution & Selection and before Forces, Motion & Momentum.

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

    Wrapping a wire into a coil and sending a current through it makes an…

    • insulator
    • electromagnet
    • permanent magnet

  2. Question 2

    A battery stores energy as…

    • light
    • chemical potential energy
    • kinetic energy

  3. Question 3

    A light bulb changes electrical energy into light and…

    • heat
    • sound only
    • mass

  4. Question 4

    A bar magnet has how many poles?

    • 4
    • 1
    • 2, a north and a south

  5. Question 5

    A magnet is surrounded by a…

    • battery
    • wire
    • magnetic field

  6. Question 6

    In a hydroelectric station, water stored high behind a dam is released. What happens first?

    • water falling and gaining kinetic energy
    • wires making heat
    • a lamp lighting up

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