1. ## 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 ??

2. and B0 is actually pronounced as B not ..

3. 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?

4. well, the wheel has a magnetic field given by B=-B(not)k(cap) from the centre having radius a..(a<r)

5. 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.

6. whoops sorry I forgot to add this, the spokes are non conducting and the rim's linear charge density is lambda

7. Are there any initial conditions? Is the wheel already turning at the moment the field gets turned off?