DAY 4 – DAW February

Magnetic shell, uniformly magnetized sphere; Ferromagnetic materials, hysteresis, energy loss. Biot-Savart law, Ampere’s law,

Questions:

Q 1. State Biot-Savart law. Calculate the magnitude of axial magnetic induction due to a circular loop of area A carrying current I. [15 marks]

Q 2. A uniformly magnetised sphere of radius $R$ has magnetization $\vec M=M_0\hat z$. If the scalar magnetic potentials inside and outside the sphere are given as under

$$\phi_m=\frac{M_o}{3}Z;r\le R$$

and

$$\phi_m=\frac{M_o}{3}\frac{R^3}{r^2}\cos \theta ;r> R$$

where $r, \theta$ are two spherical coordinates, find the magnetic field inside and outside the sphere. [15 marks]

Video Solution at 11 pm