why the ploes of permanent magnet are concave cylindrical in case ofa galvanometer
Answers
Answered by
1
Because it produces radial magnetic filed which is parallel to the plane of the coil giving strong and uniform magnetic field.
There is a circular pole piece inside the coil, and the magnet poles are arranged so that the air gap between them and the pole piece is the same. This is an attempt to ensure that no matter where the coil is angled it sees the same field strength and thus responds to a change in current by moving through the same angle.
In practice this trick fails to be perfect, and the scale is progressively less linear toward the ends, making analysis slightly trickier.
Similar questions