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A conducting disc of radius r rotaes wit...

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

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Velocity at a dostance `(r/2)` from the centre`
`= (r omega)/2`
`E=Blv=Bxxrxx(r omega)/2`
`=(1/2)Br^2 omega.`
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HC VERMA-ELECTROMAGNETIC INDUCTION-EXERCISE
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  2. A bicycle is resting on its stand in the east - west direction and the...

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  3. A conducting disc of radius r rotaes with a small but constant angul...

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  4. shows a conducting disc rotating about its axis in a perpendicular ma...

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  5. The magnetic field inn a region is given by vec B = veck (B0)/(L) y wh...

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  6. shows a straight, long wire carrying a current I and a rod of length l...

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  7. Consider a situation similar to that of the previous problem except th...

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  8. Shows a square frame of wire having a total resistance r placed coplan...

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  9. A rectangular metallic loop of length l and width b is placed coplan...

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  10. Shows a conducting circular loop of radius a placed in a uniform, perp...

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  11. Consider the situation shown in the figure of the previous problem. Su...

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  12. Consider a variation of the previous problem. Suppose the circular loo...

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  13. Shows a situation similar to the previous problem. All parameters are...

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  14. A wire of mass m and length l can slide freely on a pair of smooth, ve...

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  15. A uniform magnetic field B exists in a cylindrical region, shown dotte...

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  16. The current in an ideal, long solenoid is varied at a uniform rate of...

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  17. An average emf of 20 V is induced in an inductor when the current in...

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  18. A magnetic flux of 8X10^(-4) weber is linked with each turn of a 200 -...

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  19. The current in a solenoid of 240 turns, having a length of 12 cm and ...

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  20. Find the value of t/tau for which the current in an LR circuit builds ...

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