question

(a)  draw a schematic diagram of an ac generator. explain its working and obtain the expression for the instantaneous value of the emf in terms of the magnetic field b,number of turns n of the coil of area a rotating with angular frequency . show how an alternating emf is generated by a loop of write rotating in a magnetic field.
 (b) a circular coil of radius 10 cm and 20 turns is rotated about its vertical diameter with angular speed of 50 rad  in a uniform horizontal magnetic field of 
(i) calculate the maximum and average emf induced in the coil.
(ii) if the coil forms a closed loop of resistance 10, calculate the maximum current in the coil and the average power loss due to joule heating.

 

 

 

 

 

 

 

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