question_answer

For an ideal toroid, an observer starts travelling from centre of toroid along radial direction. Which of the following diagram best describes the magnetic field variation observed by him?

A)                                           

B)

C)                                        

D)  

Correct Answer: B

Solution :

For an ideal toriod the magnetic field outside it becomes zero and uniform magnetic field exists across the cross-section of toroid which can be given by \[B={{\mu }_{0}}ni\] (same as solenoid)