PHYSICS · Multi-part · CBSE · Physics · Moving Charges and Magnetism · Moving Charges and Magnetism
Problem
Consider an ideal, very long solenoid carrying a steady current.
(i) Explain why the magnetic field outside such a solenoid is practically negligible compared with the field inside.
(ii) When the current in the solenoid flows clockwise as viewed from one end, identify which end behaves as the north pole. Justify your answer using an appropriate rule.
(iii) Describe qualitatively how the magnitude of the interior magnetic field changes if the number of turns per unit length of the solenoid is doubled while the current remains the same.