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A ceiling fan having 3 blades of length 80 cm each is rotating with an angular velocity of 1200 rpm. The magnetic field of earth in that region is 0.5 G and angle of dip is 30 . The emf induced across the blades is N 10-5 V. The value of N is .
32
Vertical component: BV=B 30 =0.5 10-4 12= 14 10-4 T
=1200 rpm= 2 120060=40 rad/s
= 12BV l2= 12 14 10-4 40 (0.8)2
=32 10-5 V
N=32
Answer: 32
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