A length L of wire carries a steady current I. It is bent first to for – McqOptions

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1.	A length L of wire carries a steady current I. It is bent first to form a circular plane coil of one turn. The same length is now bent more sharply to give a double loop of smaller radius. The magnetic field at the centre caused by the same current is [NCERT 1980; AIIMS 1980; MP PMT 1995, 99]
A.	A quarter of its first value
B.	Unaltered
C.	Four times of its first value
D.	A half of its first value
Answer» D. A half of its first value

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