Grade 9 · Science · Unit 13 of 17
Energy & Magnetism
Conservation of energy, efficiency and electromagnets.
What your child practises
Practises the law of conservation of energy, potential and kinetic energy, efficiency, and the link between electric current and magnetic fields in electromagnets and generators.
Manitoba Curriculum learning outcome: SCI.9.E.9, SCI.9.E.11 · conservation of energy, efficiency and electromagnetism
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
A light bulb changes electrical energy into light and…
- sound only
- mass
- heat
heat
Hint: Some energy is always given off as heat.
Question 2
Which energy source is renewable?
- natural gas
- coal
- wind
wind
Hint: Wind is naturally replaced.
Question 3
A battery stores energy as…
- kinetic energy
- light
- chemical potential energy
chemical potential energy
Hint: Chemical reactions release it as electrical energy.
Question 4
Which change makes an electromagnet stronger?
- removing the iron core
- using a shorter battery life
- adding more turns of wire
adding more turns of wire
Hint: More turns or more current give a stronger field.
Question 5
Energy stored in a stretched spring is…
- kinetic energy
- potential energy
- sound energy
potential energy
Hint: Stored energy is potential.
Question 6
Which statement shows conservation of energy?
- A ball makes new energy when it bounces
- A ball's lost kinetic energy shows up as heat and sound after it lands
- A ball has no energy at the top of a throw
A ball's lost kinetic energy shows up as heat and sound after it lands
Hint: The total energy stays the same.