Question

A steady current flows in a straight wire.Gradually, the current in the wire is increased.What happens to the magnetic field when the current increases? 1.Direction of magnetic field reverses
2.Strength of magnetic field increases
3.Strength of magnetic field decreases
4.The magnetic field remains the same

Answer 1

Answer:

Explanation:

If you hold a compass near a wire through which current is flowing, the needle on the compass will be deflected.

Since compasses work by pointing along magnetic field lines, this means that there must be a magnetic field near the wire through which the current is flowing.

The magnetic field produced by an electric current is always oriented perpendicular to the direction of the current flow. Below is a sketch of what the magnetic field around a wire looks like when the wire has a current flowing in it. We use \(\vec{B}\) to denote a magnetic field and arrows on field lines to show the direction of the magnetic field. Note that if there is no current there will be no magnetic field.