In other words they are not attracted to, but rather slightly repelled by the magnetic field. These substances are said to have a negative magnetic susceptibility . Paramagnetic substances also exhibit no magnetic properties outside a magnetic field. When placed in a magnetic field, however, these substances exhibit a slight positive interaction with the external magnetic field and are slightly attracted. The magnetic field is intensified within the sample causing an increase in the local magnetic field.
Ferromagnetic substances are quite different.
When placed in a magnetic field they exhibit an extremely strong attraction to the magnetic field. The local magnetic field in the center of the substance is greatly increased. An object that has become permanently magnetized is referred to as a permanent magnet. The protons have a positive charge and the neutrons have a neutral charge. The atomic number represents the number of protons in the nucleus.