Two infinitely long straight parallel wires carry equal currents ‘i’ in the same direction and are 2 m apart. Magnetic induction at a point which is at same normal distance $\sqrt{2} \mathrm{m}$ from each wire has magnitude 

Two circular coils X and Y, having equal number of turns and carrying currents in the same sense, subtend same solid angle at point O. If the smaller coil X is midway between O and Y and if we represent the magnetic induction due to bigger coil Y at O as B_y and that due to smaller coil Y at O as B_x, then find the ratio B_x/B_y.