Right hand rule is used to determine the direction of the magnetic force field. This can be determined in case of magnetic force acting on a charge or in case of a wire carrying electric current.
1.To find the direction of Magnetic force acting on a charge in the magnetic field we use the right hand rule.Consider a charge in a magnetic field. Suppose the charge is moving and that the charge has a velocity that is acting in perpendicular to the magnetic field direction. Since the charge is in the magnetic field, a magnetic force will be acting on the charge.
Right hand rule is applicable to the theoretical flow of current and to positive charges. The theoretical flow of current is also called conventional current which flows from positive to negative end.
The direction of the magnetic field on the charge is determined using the fingers of the right hand.The index finger points at the direction of the movement of the charge. Middle finger points tothe direction of the magnetic field, and then the thumb direction gives the direction of the magnetic force on the charge.
2.Magnetic force also comes into existence around a current carrying wire. In order to determine the direction of the magnetic force around the current carrying wire, right hand rule can be used.
In this case
Here the fingers of the right hand are curled around the wire in the form of a half circle and the thumb is pointed in the direction of the current by convention which is opposite to the actual flow of current. The curled fingers give the direction of the magnetic force field around the wire.
Right hand rule was proposed in the late 1800s by British physicist John Ambrose Fleming. This rule is popularly used to find the direction of the magnetic field around a current carrying wire and the magnetic force acting on a charge in the magnetic field. This rule is easy to remember and has several applications in the scientific field.