Question

Problem 4. The generator coil shown in the figure below is rotated through one-fourth of a revolution (from θ = 0o to θ = 90o ) in 15.0 ms. The 200-turn circular coil has a 5.00 cm radius and is in a uniform 1.25 T magnetic field. What is the average emf induced?

1 Carbon brush Carbon brush B N. S Path of motion Coil rotated by mechanical means 90°

Answer 1

25cm B se Isinal magnene flux, = BANCOSO Bemagnena field = 1.25T Azarea of coil = 73 314x6x0=3) /rodus A=78.5x10-4 m2 Na number of turns 2 200 - -angle between and normal to coil =90 [plane of coll makes [zero degree with B] BANCOS 90=0 Final flux, P2= BANCOSO [plane makes 900. Here normal makes oo] P2 = 1.25 x 38.5x10-4x 200 = 1.9625 wb change in fluxe, do=82-8. = 1.9625 Wb time = dt = 15m= 15x10 3 see End induced, e=de = 1.9625 Me = 130.83 volt 15x 10-3