A long circular tube of length 10 m and radius 0.3 m carries a current I along its curved surface as shown. A wire-loop of resistance 0.005 Ω and of radius 0.1 m is placed inside the tube with its axis coinciding with the axis of the tube. The current varies as I = I 0 cos ( 300 t ) where I 0 is constant. lf the magnetic moment of the loop is N μ 0 I 0 sin ( 300 t ) , then ` N ' is 6 8 7 9 be obtained by heating?