Objective of the experiment: To prove the Inverse Cube Law for magnetic bipolarity.

Theory: Magnetic fields are one of the physical quantities that we cannot see with the naked eye, but we can perceive their existence. Both electricity and magnetism originate from charges. However, the key difference between the two is that an electric field can be generated by stationary charges, while a magnetic field only involves moving charges. A magnetic field only exerts force on moving charges. In physics, the magnetic field is represented by the letter B, and the standard unit in the MKS system is the Tesla, where one Tesla equals one Newton per Ampere meter. Magnetic fields can also be measured in Gauss, with the relationship between Tesla and Gauss being that one Tesla equals ten thousand Gauss. The Tesla is a very large unit for measuring magnetic fields. The magnetic field intensity B along the axis of a bar magnet at a distance r from the center is directly proportional to the magnetic moment M and inversely proportional to the cube of the distance, specifically in cases where the distance r is much greater than the length of the bar magnet.

Procedure:

1. Connect the magnetic field sensor to the application.

2. Record the observed magnetic field value B0.

3. Experiment by placing different shaped magnets at varying distances (0-10 cm) from the sensor and record the magnetic field value B at each position.

4. Plot the relationship between B and r, and B and 1/r^3.