With the help of a labelled circuit diagram illustrate the pattern of field lines of the magnetic field around a long current carrying straight conducting wire. How is the right hand thumb rule useful to find direction of magnetic field associated with a current carrying conductor?
The magnetic field lines around a straight conductor (straight wire) carrying current are concentric circles whose centers lie on the wire. Figure below shows the field lines.
Right hand thumb rule states that if a current carrying straight conductor is supposedly held in the right hand with the thumb pointing towards the direction of current, then the fingers will wrap around the conductor in the direction of the field lines of the magnetic field.
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