Question

Which of the following statements are correct?
(A) Electric monopoles do not exist whereas magnetic monopoles exist.
(B) Magnetic field lines due to a solenoid at its ends and outside cannot be completely straight and confined.
(C) Magnetic field lines are completely confined within a toroid.
(D) Magnetic field lines inside a bar magnet are not parallel.
(E) $\chi =-1$ is the condition for a perfect diamagnetic material, where $\chi$ is its magnetic susceptibility.
Choose the correct answer from the options given below:

• A. (C) and (E) only
• B. (B) and (D) only
• C. (A) and (B) only
• D. (B) and (C) only

Answer 1

Answer: (A)

Statement (C) is correct because, the magnetic field outside the toroid is zero and they form closed loops inside the toroid itself.
Statement $(E)$ is correct because we know that super conductors are materials inside which the net magnetic field is always zero and they are perfect diamagnetic.
${\mu }_r=1+\chi$
$\chi =-1$
${\mu }_x=0$
For superconductors.