Magnetic Flux

Magnetic flux is defined in the same way as electric flux is defined in chapter ELECTRIC CHARGE AND FIELD. Magnetic flux through a plane of area D placed in a uniform magnetic field is given by

where θ is the angle between the vectors and d See figure 4. Magnetic flux through the entire surface can be calculated by integrating the dot product . d as given below

Magnetic flux is a scalar quantity. Its unit is Weber (or Volt-sec) or T-m2. Its CGS unit is Maxwell (Mx).

  1. For a body present in a field (uniform as well as nonuniform), outward flux is taken to be positive while inward flux is taken to be negative.
  2. Magnetic field may or may not be zero if magnetic flux θ B = 0 as positive flux may be equal to negative flux. But if = 0, the flux will necessarily be zero.
  3. Gauss's law for magnetism is given by

    This is due to the fact that magnetic lines of force are closed curve and thus, net flux through a closed surface is always zero.
  4. Flux linked with a surface changes, if magnetic field B, area A or orientation or any combination of these changes.

CBSE Electromagnetic Induction ( With Hint / Solution)
Class XII (By Mr. Ashis Kumar Satapathy)
email - [email protected]

Electromagnetic Induction