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Consider the situation shown in the figu...

Consider the situation shown in the figure of the previous problem. Suppose the wire connecting O and C has zero resistance but circular loop has a resistance R uniformly distributed along its length. The rod OA is made to rotate with a uniform angular speed `omega` as shown in the figure. Find the current in the rod when `ltAOC = 90^@`.

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The two resistances `(r/4) and (3r)/(4) are in parallel.`
Equivalent resisatance R'=((r/4)xx(3r/4)/®=(3r)/(16)`
`e=Bvl= Bxx(a/2) omega xxa`
`=(Ba^2 omega)/2`
`e/(R')=(Ba^2 omega)/(2R')=(Ba^2 omega)/(2xx 3r//16)`
`=(Ba^2 omega 16)/(2xx3r)=(8Ba^2 omega)/r`.
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HC VERMA-ELECTROMAGNETIC INDUCTION-EXERCISE
  1. A rectangular metallic loop of length l and width b is placed coplan...

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

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

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

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

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

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

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

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

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

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

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

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  13. An inductor coil carries a steady state current of 2.0 A when connect...

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  14. A coil having inductance 2.0 H and resistance 20 Omega is connected t...

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  15. A coil of resistance 40 Omega is connected across a 4.0 V battery. 0...

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  16. An inductor of inducance 5.0 H, having a negligible resistance, is con...

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  17. The time constant of an LR circuit is 40 ms. The circuit is connected...

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  18. An LR circuit has L = 1.0 H R =20 Omega. It is connected across an e...

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  19. What are the values of the self induced emf in the circuit of the pr...

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  20. An inductor-coil of inductance 20 mH having resistance 10 Omega is jo...

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