Hans Christian Oersted (1777-1851) observed that a compass needle suffers a deflection when placed n

Question

Hans Christian Oersted (1777-1851) observed that a compass needle suffers a deflection when placed near a metal wire carrying an electric current. This discovery gave the first evidence of a connection between electric and magnetic phenomena. Andre Ampere (1775-1836) grasped the significance of Oersted's discovery. He carried out a large series of experiments to explore the relationship between current electricity and magnetism. On the basis of experiments, he hypothesised that all magnetic phenomena are due to circulated electric currents. Later on many devices such as electromagnets, electric motors, microphones, electric generators, etc. were developed on the basis of magnetic phenomena.\ When a current flows through a straight conductor, a magnetic field is produced around it. Consider the following statements about this field:\ I. The direction of the magnetic field of a current carrying straight conductor is determined by right-hand thumb rule.\ II. A charged body placed in this field experiences a force whose direction is given by Fleming's lefthand rule.\ III. The magnetic field lines around a current carrying straight conductor are in the form of concentric circles with the conductor as the centre.\ The correct statement(s) is/are :

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(d) : Right hand thumb rule says that straight thumb of right hand points in the direction of electric current and direction of curled finger represents the direction of magnetic field in a straight conductor. Flemming's left hand rule gives direction of force experienced by current carrying conductor in magnetic field. The magnetic field due to straight conductor is in the form of concentric magnetic lines.\