Magnetic field induction at the centre O of a square loop of side a carrying current I as shown in figure.

Options

A. `(mu_(0)l)/(sqrt2 pia)`
B. `2sqrt2 (mu_(0)l)/(pia)`
C. zero
D. `(mu_(0)l)/(2pia)`

Answer

C

Explanation

AbB and DC, AD and BC are the two current carrying pairs. They are so situated that currents of each pair produce equal and opposite magnetic fields at the centre O of the loop. Hence, the resultant magnetic field induction at the centre O of the loop is zero.