Question

Two coplanar and concentric circular loops of wire carry currents of 1 5.00 A and 12 3.00 A in opposite directions as shown in the figure. (a) If r 12.0 cm and r2 9.00 cm, what is the magnitude and the direction of the net magnetic field at the center of the two loops? (b) Let ri remain fixed at 12.0 cm and let 12 be variable. Determine the value of r2 such that the net field at the center of the loops is zero. To

Answer 1

Magnetic field at the cente of the circular loop of radius ri 2r ㄫㄨ η = radius of the outer loop-12.0e-2 m I,--5.00 A consider themagneticfield pointing in ward as negativeand outof plane of pageaspositive Magneticfieldat the centre of the circular loop of radius r, ㄫㄨ z - radiusof the inner loop -12.0e-2m I2- 3.00A we plug the valuesin hand whileusing the relationgives net magnetic field at the centre of loop= 2,212 (b) if thenet magneticfield B 0 252r, we plug the valuesin hand whileusing the relationgives r, = 7.2cm