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Consider the circuit shown in the fig. s...

Consider the circuit shown in the fig. sliding contact is being pulled towards right so that the resistance in the circuit is increasing. Its valve at the instant shown in `12 Omega`. Will the current be more then 0.50 A or less than it at this instant?

Text Solution

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As the sliding contact is being pulled, the current in the circuit changes
An induced emf`varepsilon =- L(di)/(dt) is produced across the inductor
The net emf in the circuit is `6 V - L (di)/(dt)` and hence the current is ` i= (6 V - L(di)/(dt))/(12 Omega) at the instant shown
now the resistance in the circuit is increasing, the current is decreasing and `so(di)/(dt)` is nagative thus, the numerator of (i) is more then 6 V and hence i is greater then `(6 V)/ (12 Omega) =0
50 A .
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HC VERMA-ELECTROMAGNETIC INDUCTION-EXERCISE
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  5. A conducintg circular loop having a redius of 5.0cm, is placed perpe...

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  6. A coducting circular loop of area 1mm^2 is placed coplanarly with a lo...

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  7. A square- shaped copper coil has edges of length 50cm and contains 50 ...

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  9. A conducting loop of area 5.0 cm^2 is placed in a magnetic field which...

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  10. Shows a conducting square loop placed parallel to the pole faces of a ...

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  11. A conducting square loop having edges of length2.0 cm is rotated throu...

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  12. A conducting loop of face area A and resistance R is plaed perpendicul...

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  13. A long slenoid of radius 2 cm has 100 turns/cm and carries a current o...

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  14. Shown a metallic square frame of edga a in a vertical plane. A uniform...

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  15. The north pole of a magnet is brought down along the axis of a horizon...

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  16. A wire loop confined in a plane is rotated in its open plane with some...

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  17. Shown a square loop of side 5 cm beign moved towards right at a consta...

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  18. Find the total heat produced in the loop of the previous problem durin...

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  19. A unifrom magnetic field B exists in a cylindrical region of radius 10...

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  20. Shows a square loop having 100 turns, an area of 2.5 X10^(-3) m^2 and...

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  21. Shown a circular coil of N turns and radius a, connected to a battery...

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