Two coils, battery and galvanometer: Testing Experiment

Aim

Predict the reading on the galvanometer given the six situations described below.

Prior Knowledge

1. Magnetic Field.
2. Model based on prior observations.

Description of the Experiment

The experiment consists of two coils. One coil is connected to the galvanometer which will register currents flowing through the coil. The other coil connected to a switch and a 9V battery which will cause a current to flow through the coil when the switch is closed.

The experiment consists of six different ways in which the two coils interact. For each situation, predict what the reading on the galvanometer will be.

1. The coils are laid on the table several cm apart. The switch connected to the right hand coil is closed and opened. Predict what will happen to the current in the left hand coil (connected to the galvanometer).
2. The coil connected to the galvanometer is placed on top of the coil connected to the switch and battery. What happens to the current in the top coil as the switch is opened and closed? What happens when the switch remains closed?
3. The coil connected to the galvanometer is placed vertically in the middle of the coil connected to the switch and battery which is lying horizontally on the table. What happens to the current in the verically oriented coil as the switch is opened and closed?
4. The switch connected to the coil lying on the table is closed so that a constant current is flowing through the coil. The coil connected to the galvanometer is held above and rotated about a horizontal axis. Predict what will happen to the current in the coil connected to the galvanometer as it is rotated.
5. Again, a steady current is flowing through the coil resting on the table. The coil connected to the galvanometer is raised rapidly up and down above the first coil. Predict what will happen to the current in the coil connected to the galvanometer.
6. The above situation is repeated but the coil is moved down very slowly towards the coil resting on the table. Predict what will happen to the current in the coil. Compare to the situation where the coil is moved quickly.

Addtional Information

Here is a simplified diagram of the magnetic field produced by a circular coil with a current flowing in it. It may help you understand what is going on.

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