10 minutes maximum! Can you do it in 5?

1. A copper wire has a magnetic field around it if...

  • A. it has been magnetised.
  • B. there is a current flowing through it.
  • C. it is twisted into a coil.
  • D. it is heated up.

Q 2-4. The diagram below shows a copper wire between 2 magnets.

copper wire in a magnetic field

 

2. In which direction is the magnetic field?

  • A. N to S
  • B. S to N
  • C. A to B
  • D. B to A

3. A current flows through the wire from A to B. Which way is the wire pushed?

  • A. To the right
  • B. To the left.
  • C. Upwards.
  • D. Downwards.

4. If we want the force on the wire to be reversed, which way must current flow?

  • A. N to S
  • B. S to N
  • C. A to B
  • D. B to A

5. If we want the wire to be pushed to the right, which way must current flow?

  • A. A to B
  • B. B to A
  • C. Use an alternating current.
  • D. This is not possible using a current.
Q6-9. The magnets and wire are re-arranged. A current flows in the wire as show by the arrow. horizontal wire in a magnetic field

6. Using the left-hand rule, what represents the magnetic field?

  • A. Thumb.
  • B. First finger.
  • C. Second finger.
  • D. Third finger.

7. In which direction will this wire be pushed?

  • A. To the left.
  • B. To the right.
  • C. Upwards.
  • D. Downwards.

8. There are several ways to increase the size of the force on the wire. Which of these will not work?

  • A. use a wire with less mass.
  • B. Increase the current.
  • C. Increase the strength of the magnetic field.
  • D. Increase the length of wire in the field.

9. What could be done to push the wire in the opposite direction, with twice the force?

  • A. Switch the N and S poles of the magnets round.
  • B. Double the current.
  • C. Switch the direction of the current AND the N and S poles.
  • D. Double the current AND switch the N and S poles.

10. This coil of wire has a current flowing through it which makes the coil move.

rectangular coil in magnetic field

 

Which way does the coil move?

  • A. To the left.
  • B. To the right.
  • C. Rotates clockwise.
  • D. Rotates anti-clockwise.