• Bar magnet
• Horseshoe magnet
• Compass needle mounted on a pivot point
• Iron fillings
• Piece of white cardboard

The forces of interaction between permanent magnets is demonstrated by bringing a bar magnet and then a horseshoe magnet near a compass needle which was initially aligned in the earth's magnetic field. Magnetic field lines are demonstrated by sprinkling iron fillings on a piece of cardboard which is placed over a bar magnet and then over a horseshoe magnet.

• Car battery (12 V)
• High current wire
• Knife switch
• Connecting wires
• Magnetic Compass

This demonstration emphasizes the magnetic field produced by the motion of charged particles. A wire capable of carrying a high current is connected directly to a 12 V car battery through a high capacity knife switch. The switch is thrown closed for a short time and the effect of the current on a nearby compass needle is observed. (It is important to immediately reopen the switch to prevent overheating.)

• Coil
• Car battery (12 V)
• Connecting wires
• Iron fillings
• Piece of white cardboard

A coil is connected to a 12 V car battery. The magnetic field lines are shown by sprinkling iron fillings on the surface of a piece of cardboad which is placed over the coil.

• Car battery (12 V)
• Straight wire
• Piece of white cardboard
• Connecting wires
• Knife switch
• Iron fillings

The two ends of a long wire are connected to a 12 V car battery through a high capacity knife switch. The magnetic field lines near the wire are demonstrated with the aid of iron fillings sprinkled over a cardboard surface. When the switch is closed for a short time the iron fillings are caused to line up in circles around the wire. (It is important to immediately reopen the switch to prevent overheating.)

• Cathode ray tube
• High voltage power supply
• Bar magnet
• Connecting wires

A cathode ray tube, in which the direction of the electron beam may be monitored along its length, is connected to a high voltage power source. A magnet is then brought near the tube and the deflection of the beam is observed. In the video desription, the classical magnetic force due to the motion of a charged particle is being emphasized, while the effect of the particle's intrinsic magnetic moment is not considered.

• Two car batteries (12 V each)
• Long conducting wires
• Knife switch

Two parallel conducting wires are connected to a bank of two 12 V car batteries through a high capacity knife switch. The wires are arranged close to one another such that the currents are either in the same direction or in opposite directions. For each case, the knife switch is then closed for a short time and the magnetic force on each wire is observed. (It is important to immediately reopen the switch to prevent overheating.)

• Car battery (12 V)
• Horseshoe magnet
• Knife switch
• Connecting wires

A circuit is set up with wires directly connected to the terminals of a 12 V car battery through a high capacity knife switch. One of the wires is placed between the poles of a strong horseshoe magnet. The switch is then closed for a short time and the magnetic force on the wire is observed. The experiment is repeated with the magnetic field direction reversed. (It is important to immediately reopen the switch to prevent overheating.)

• Compass needle mounted on a pivot point
• Horseshoe magnet

The poles of a compass needle are shown to be reversed as the needle is forced into the opposing magnetic field of a much stronger magnet.

• Car battery (12 V)
• Coil
• Connecting wires
• Iron rod
• Knife Switch

A coil is connected to a 12 V car battery through a knife switch. A non-magnetized piece of iron is placed in the core of the coil and is shown to become magnetized as the switch is closed and the magnetic field of the coil is established.

• Demonstration electric motor
• Car battery (12 V)
• Knife switch
• Connecting wires

A demonstration DC electric motor is connected to a 12 V car battery through a knife switch. When the switch is closed, the forces and torques on the rotor of this motor are demonstrated.