Purpose: To demonstrate the magnetic field lines that surround a current carrying conductor and a solenoid.

It consists of a coilboard pierced by a solenoid and the two current carrying wires leading to it. A low voltage high current D.C. power supply provides the source of current (e.g., car battery).

Place the board on the Cannon Document camera. Switch to 12V setting and turn on the power supply. Turn knob until current is about 10A (just under the red). Sprinkle iron filings
on the board. Gently tap the board with a pencil until the filing align with the magnetic field.

Caution: Do not leave the power supply on for extended periods of time since the current is very large and thing really heat up.

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