A non-conducting, uniformly charged disc of surface charge density o, radius R and negligible thickness is rotating about its axis with an angular velocity w. (a) Consider a thin circular loop of radius dr at a distance r from the disk center as shown on the picture. Show that the charge on the thin loop is given by dq=2.tor dr. (b) What is the magnetic field dB at the center of the disc, created by the rotating charge dq calculated in (a)? Hint: what is the current dI due to the rotation? (c) Calculate the total magnetic field B at the center of the disc. (d) What is the direction of B?

A non-conducting, uniformly charged disc of surface charge density o, radius R and negligible thickness is rotating about its axis with an angular velocity w. (a) Consider a thin circular loop of radius dr at a distance r from the disk center as shown on the picture. Show that the charge on the thin loop is given by dq=2.tor dr. (b) What is the magnetic field dB at the center of the disc, created by the rotating charge dq calculated in (a)? Hint: what is the current dI due to the rotation? (c) Calculate the total magnetic field B at the center of the disc. (d) What is the direction of B?

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter11: Magnetic Forces And Fields

Section: Chapter Questions

Problem 108CP: A wire ismade into a circular shape of radius R and pivoted along a central support.The two ends of...

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