Figure show the circular coil carrying current l kept very close but not touching at a point A on a straight conductor carrying the same current l . The magnitude of magnetic induction at the centre of the circular coil will be

Step-by-step solution

Magnetic induction at the centre of circular current carrying loop, B 1 = μ 0 i 2 r (downward direction) Magnetic induction at the centre O due to a straight wire, B 2 = μ 0 2 π . i r (upward direction) Net magnetic induction at O, B = B 1 - B 2 = μ 0 i 2 r - μ 0 2 π . i r = μ 0 i 2 r 1 - 1 π [downward direction] Hence, there are no options correct.