Magnetic force on moving charges, and how motors work
Grade 11 Science Worksheet - Challenge Me
Circle the best answer, or write your answer on the line.
A motor coil has 40 turns, and each side has 0.04 m in a 0.25 T field. It carries 0.5 A. What force acts on one side, Ari?
A motor coil has 25 turns, and each side has 0.03 m in a 0.4 T field. It carries 1.2 A. What force acts on one side, Esme?
A proton moves straight across a magnetic field. What does the field do to its path, Jun?
- Speeds it up in a straight line
- Leaves it unchanged
- Bends it into a curve
A proton sits still in a magnetic field. What magnetic force acts on it, Kira?
- A force toward north
- None
- A force toward south
Milo says a wire lying along magnetic field lines feels the biggest force. Agree or disagree?
- Agree: along the field is strongest
- Disagree: it feels none
- Agree: the field pushes it along
Noah says a current running along a field still gets pushed sideways. Agree or disagree?
- Agree: any current in a field is pushed
- Disagree: it must cross the field
- Agree: fields push along their lines
Pia says a simple motor would spin the same way without its commutator. Agree or disagree?
- Disagree: it would rock back and forth
- Agree: the commutator is just decoration
- Agree: the magnet keeps it spinning
A loudspeaker has a coil attached to a cone, sitting in a magnet's field. What moves the cone, Ren?
- Air pressure from the room
- Heat from the magnet
- Changing current in the coil
What part of an electric fan makes the blades turn, Tala?
- A light bulb
- A battery alone
- A motor
A toy car's motor is wired to its battery the other way round. What happens, Zee?
- It drives faster
- It drives the other way
- It stops and won't start again