Describe the direction of magnetic field lines around a straight conductor and the factors affecting its strength.

b) The rule used to indicate the direction of the magnetic field lines is the Right-Hand Grip Rule (also known as the Right-Hand Thumb Rule).

c) Two conclusions regarding the nature of the magnetic field around a straight conductor carrying current are:

• The magnetic field lines form concentric circles around the conductor.
• The strength of the magnetic field decreases as the distance from the conductor increases.