Question 81: Magnetism and Matter

Question

A perfectly diamagnetic sphere has a small spherical cavity at its centre, which is filled with a
paramagnetic substance. The whole system is placed in a uniform magnetic field $\overrightarrow B $
. Then the field
inside the paramagnetic substance is :
![](https://imagex.cdn.examgoal.net/jgy2xukf3us437/38c55d8d-40fb-4f8e-94fd-fcb50f09d6fb/cca36030-f743-11ea-8293-3b6cc591631c/file-jgy2xukf3us438-243w.png)

Accepted Answer

A perfect diamagnetic substance will completely expel the magnetic field. Therefore, there will be no magnetic field inside the cavity of sphere. Hence the paramagnetic substance kept inside the cavity will experience no force.

Answer

$\overrightarrow B $

Answer

zero

Answer

much large than $\left| {\overrightarrow B } \right|$ and parallel to $\overrightarrow B $

Answer

much large than $\left| {\overrightarrow B } \right|$ but opposite to $\overrightarrow B $

Magnetism and Matter

A perfectly diamagnetic sphere has a small spherical cavity at its centre, which is filled with a paramagnetic substance. The whole system is placed in a uniform magnetic field \overrightarrow B . Then the field inside the paramagnetic substance is :

Choose the correct answer: