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A metallic wire is folded to form a squa...

A metallic wire is folded to form a square loop a side `'a'`. It carries a current `'I'` and is kept perpendicular to a uniform magnetic field. If the shape of the loop is changed from square to a circle without changing the length of thw wire and current, the amount of work done in doing so is

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`W=`Find `P.E.-`initial`P.E.`
`X=-M_(f)B-(M_(i)B),W=iB(A_(i)-A_(f))`
`W=iBa^(2)[1-(4)/(pi)]`
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NARAYNA-MOVING CHARGES AND MAGNETISM-EXERCISE - 4
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  2. A particle of charge +q and mass m moving under the influnce of a unif...

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  4. A current loop ABCD is held fixed on the plane of the paper as shown i...

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  5. A current loop ABCD is held fixed on the plane of the paper as shown i...

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  6. A current carrying loop is placed in the non-uniform magnetic field wh...

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  9. A circular coil of 30 turns and radius 8.0 cm carrying a current of 6....

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  10. Two Concentric circular coils X and Y of radii 16 cm and 10cm lie in ...

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  11. Toroid has a core (non-ferromagnetic) of inner radius 25 cm and outer ...

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  12. A uniform magnetic field of 1*5T is in cylindrical region of radius 10...

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  13. A cubical region of space is filled with some uniform electric and mag...

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  14. Two long wires carrying current I1 and I2 are arranged as shown in fig...

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  15. A current carrying loop consists of 3 identical quarter circles of rad...

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  18. A 100 turn rectangular coil ABCD (in XY plane) is hung from one arm of...

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  19. A rectangular conducting loop consists of two wires on two opposite si...

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  20. An electron and a position are released from (0, 0, 0) and (0, 0, 1*5R...

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  21. Five long wires A, B, C, D and E, each carrying currentl I are arrange...

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