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9th grade · Science · Unit 10 of 28

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.

New York State Learning Standards learning standard: HS-PS3-1; HS-PS2-5 · conservation of energy and efficiency, 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 New York

In the New York State Learning Standards, this is unit 10 of 28 in 9th grade Science, after Forces, Motion & Momentum and before Circuits & Ohm's Law.

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: New York State Education Department (NYSED)

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 magnet is surrounded by a…

    • battery
    • wire
    • magnetic field

  2. Question 2

    A roller coaster at its highest point has the most…

    • sound energy
    • kinetic energy
    • gravitational potential energy

  3. Question 3

    A moving electric charge produces a…

    • magnetic field
    • a sound wave
    • a shadow

  4. Question 4

    A light bulb changes electrical energy into light and…

    • heat
    • sound only
    • mass

  5. Question 5

    As a roller coaster speeds down a hill, potential energy is changing into…

    • nuclear energy
    • kinetic energy
    • magnetic energy

  6. Question 6

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

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

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