Current Loop in Magnetic Field - Physics Demonstrations - Current Loop in Magnetic Field | Physics Undergraduate Labs

The copper solder wick suspension is fragile and will melt if excessive current flows through it. Never exceed 6 volts and minimize the duration of current flow. Turn off the current immediately after demonstrating each deflection.

Purpose

A current-carrying coil suspended in a horseshoe magnet's field rotates to align with the field, demonstrating the torque $\vec{\tau} = \vec{\mu} \times \vec{B}$ on a magnetic dipole. Students observe the motor principle: magnetic forces on current-carrying conductors produce rotation toward equilibrium.

Wire coil suspended between poles of a horseshoe magnet on a wooden base, connected via red wires to a Xantrex DC power supply reading 3.17 V

Figure 1: The wire coil hangs between the horseshoe magnet's poles via a copper solder wick. The DC power supply provides adjustable voltage to control the current through the coil.

Safety Warnings

Warning: Thermal Damage Warning

Purpose