In permanent magnet devices this is usually done by increasing the gap between the magnet arrays, or in electromagnetic devices by varying the current in the magnet coils.
In electromagnetic devices the magnetic field is changed by varying the current in the magnet coils. In permanent magnet devices this is usually done by increasing the gap between the magnet arrays.
In permanent magnet devices this is usually done by increasing the gap between the magnet arrays. In electromagnetic devices the magnetic field is changed by varying the current in the magnet coils.
In permanent magnet devices this is usually done by increasing the gap between the magnet arrays. In electromagnetic devices the magnetic field is changed by varying the current in the magnet coils.