A straight wire of length \[({{\pi }^{2}})\] metre is carrying a curre – McqOptions

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1.	A straight wire of length \[({{\pi }^{2}})\] metre is carrying a current of 2A and the magnetic field due to it is measured at a point distant 1 cm from it. If the wire is to be bent into a circle and is to carry the same current as before, the ratio of the magnetic field at its centre to that obtained in the first case would be [Haryana CEE 1996]
A.	50 : 1
B.	1 : 50
C.	100 : 1
D.	1 : 100
Answer» C. 100 : 1

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