NOOTAN KUMAR MITTAL ISC CLASS 12th PHYSICS Chapter-7 (Moving Charges and Magnetic Field)

              CHAPTER-7

Moving Charges and Magnetic Field.

*. Concept of Magnetic Field.

The region near a magnetic, where a magnetic needle experiences a torque and rest in the definite direction is, called 'magnetic field'.

*. Oersted's Experiment.

Moving charge produce magnetic field in the surrounding space.

*. Magnetic Field due to Current-Conductor : Biot-Savart's Law

The  Biot-Savart Law relates magnetic fields to the currents which are their sources. In a similar manner, Coulomb's law relates electric fields to the point charges which are their sources. Finding the magnetic field resulting from a current distribution involves the vector product, and is inherently a calculus problem when the distance from the current to the field point is continuously changing.

*. Rules to Determine the Direction of Development Magnetic Field.

(I)Right hand thumb rule is used to determine the direction of magnetic field around the straight conductor carrying current.

(ii) Fleming's left hand rule is used to find the direction of force experienced by a current carrying straight conductor placed in a magnetic field which is perpendicular to it. 

(iii) Fleming's right hand rule is used to find the direction of current induced in a coil due to its rotation in a magnetic field.

*. Application of Biot-Savart's Law.

* Ampere Circuital Law

It states that the line integral of the magnetic field vector B around any closed path is equal to times the net current I  treading the area enclosed by the path.

Numericals