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Manipal MET2018PhysicsCurrent Electricity

An electric motor operates on a 50 V supply and a current of 12 A . If the efficiency of the motor is 30 % , what is the resistance of the winding of the motor ?

Options

  1. A6
  2. B2.9
  3. C4
  4. D3.1

Correct answer

B. 2.9

Step-by-step solution

I= E-e R ...(i) and 100= ( e E ) 100 ...(ii) array lll & 30 & = e 50 100 & e & =15 ~V Thus, & R & = 50-15 12 =2.9 array

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