1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Strange Problem

  1. Dec 2, 2004 #1
    Hello
    Well i am having this strange problem in electromagnetic induction can someone help me here?
     

    Attached Files:

  2. jcsd
  3. Dec 2, 2004 #2

    Andrew Mason

    User Avatar
    Science Advisor
    Homework Helper

    It is not entirely clear to me how the diagram relates to the description but this is what it looks like: There is a wheel of radius R in a horizontal plane free to rotate about the z axis, the z axis being in the direction of [itex]\hat k[/itex]. The magnetic field is [itex]\vec B = -B_0\hat k[/itex] and extends over a 'doughnut' area from r to R. When the magnetic field collapses, Faraday's law states that there is an electro-motive force or voltage created in a closed loop which encloses the magnetic field. This emf causes the charges to move. Since the charges are 'pasted' to the rim of the wheel, the emf provides angular acceleration to the wheel.

    To find the emf you would have to use Faraday's law:
    [itex]V\Delta t = -N\Delta BA[/itex] where N = 1 (no. of windings) and A is the area of the magnetic field enclosed by the wheel rim. The [itex]\Delta t[/itex] term should fall out when you work out the angular impulse [itex]T\Delta t[/itex] in terms of [itex]V\Delta t [/itex].

    AM
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Strange Problem
  1. Strange trig problem (Replies: 5)

  2. Strange problem. (Replies: 5)

  3. Strange K.E. problem (Replies: 8)

Loading...