Magnetic field due to a rotating charged cone | IIT JEE Advanced Physics (2026)

You may have seen ways to calculate magnetic fields due to a current carrying wire loop. Can you extend this concept to a rotating charged cone? This question appeared in one of the toughest engineering entrance examinations (IIT JEE advanced 2026) which required students to solve for magnetic field created along the axis of the cone, when it is rotating with an angular velocity. In this video, we'll visualize the problem conceptually and show how familiar concepts of a current-carrying loop naturally extends to this seemingly complex geometry. By the end, you'll have a powerful conceptual framework for tackling similar problems. ------------------------------------------------------------------------------------------------------------------- Chapters 00:00 - 00:17: Intro 00:18 - 00:54: Reading the problem carefully 00:55 - 01:50: Visualization and key concepts 01:51 - 15:55: Step by step problem solving 15:56 - 16:14: Outro