A circular coil ?A? has a radius R and the current flowing through it – McqOptions

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1.	A circular coil ?A? has a radius R and the current flowing through it is I. Another circular coil ?B? has a radius 2R and if 2I is the current flowing through it, then the magnetic fields at the centre of the circular coil are in the ratio of (i.e.\[{{B}_{A}}\] to \[{{B}_{B}}\]) [CBSE PMT1993; AIEEE 2002]
A.	4 : 1
B.	2 : 1
C.	3 : 1
D.	1 : 1
Answer» E.

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