Question

How are the field lines in a uniform magnetic field ?

• A. curved
• B. parallel equidistant straight lines
• C. parallel but non-equispaced straight lines
• D. nothing can be said.

Answer 1

The correct option is B parallel equidistant straight lines

A uniform magnetic field is a magnetic field that has the same magnitude and direction throughout the region under consideration, thus the field lines need to be both parallel and spaced out evenly. The density of field lines at a specific point decide the strength of the field at that point, thus a uniform magnetic field or any uniform field for that matter must have the same number of field lines at every point under consideration.
So a uniform magnetic field would look like a bunch of parallel lines spaced out at equal distance from one another.