Q. 52

A conducting disc of radius r rotates with a small but constant angular velocity ω about its axis. A uniform magnetic field B exists parallel to the axis of rotation. Find the motional emf between the center and the periphery of the disc.

Answer :

Given:


Radius = r


Angular velocity = w


Magnetic field = B


Diagram:



Formula used:


In this case, the velocity will increase radially.


Let us consider a strip of width dx at a distance x from the centre.


Hence, induced emf of this portion will be , where B = magnetic field, dx = width of the element, x = distance of the element from the centre, w = angular velocity


Hence, integrating on both sides using proper limits, we get



=> Total motional emf (Ans)


Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Electromagnetic InductionElectromagnetic InductionElectromagnetic Induction50 mins
Source of Electromagnetic waveSource of Electromagnetic waveSource of Electromagnetic wave6 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
caricature
view all courses
RELATED QUESTIONS :