# Electromagnetic indction question...

• Jun 16th 2010, 10:15 AM
ice_syncer
Electromagnetic indction question...
There is a wheel of mass M and radius R .. now , from the centre, radius 'a' ( a < R ) there is a magnetic field given by
B = -B0 * k if r<=a where k is the unit vector
and 0 elsewhere

now suddenly, the field is switched off... what is the angular velocity of the wheel ??
• Jun 16th 2010, 10:16 AM
ice_syncer
and B0 is actually pronounced as B not .. :)
• Jun 17th 2010, 04:51 PM
Ackbeet
There seems to be some information missing here. For example, we're not told if the wheel is magnetic or not. Could you please post the problem statement in full, omitting nothing?
• Jun 19th 2010, 11:11 AM
ice_syncer
well, the wheel has a magnetic field given by B=-B(not)k(cap) from the centre having radius a..(a<r)
• Jun 19th 2010, 11:40 AM
Ackbeet
So, the wheel has a magnetic field given by your equation there. And then you suddenly turn the field off. What is that going to do, physically? Walk me through the physics.
• Jun 20th 2010, 10:18 AM
ice_syncer
whoops sorry I forgot to add this, the spokes are non conducting and the rim's linear charge density is lambda
• Jun 23rd 2010, 03:00 AM
Ackbeet
Are there any initial conditions? Is the wheel already turning at the moment the field gets turned off?