Direction of the induced current: Observational Experiment

Aim

To determine how the change in magnetic field through the coil is related to the direction of the induced current in the coil.

Prior Knowledge

  1. Magnetic field of a bar magnet.
  2. Phenomenon of electromagnetic induction.

Description of the Experiment

In this experiment you have to pay attention to the direction of the induced current to find a pattern between the direction of the current in the coil and the changes of external magnetic field through it. Note how the coil is wired. This will help you to determine the direction of the current in the coil. Observe each experiment. Draw magnetic field lines of the magnet and magnetic field lines due to the induced current in the coil. Record whether the magnetic field through the coil is increasing or decreasing. This information will help you to find a pattern.

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Questions

  1. Does the direction of the current depend on the direction of the motion of the magnet?
  2. Identify instances when the magnet is moving in the same direction but the direction of the current changes
  3. Identify instances when the magnet is moving in different directions (but with the same orientation) and the direction of the current changes.
  4. For each of the instances, draw magnetic field lines of the magnet and magnetic field lines of the field created by the induced current.
  5. Devise a general rule relating the direction of the induced current and the changes in the external magnetic field through the coil.