When an electric train is moving down a hill, the DC motor will operate as ____________(a) DC series motor(b) DC series generator(c) DC shunt motor(d) DC shunt generatorThis question was addressed to me in an interview.The query is from Applications of DC Machines topic in portion DC Machines of DC Machines

When an electric train is moving down a hill, the DC motor will operat

1.	When an electric train is moving down a hill, the DC motor will operate as ____________(a) DC series motor(b) DC series generator(c) DC shunt motor(d) DC shunt generatorThis question was addressed to me in an interview.The query is from Applications of DC Machines topic in portion DC Machines of DC Machines
Answer» Correct answer is (b) DC SERIES generator The explanation: Normally in electric TRACTION purposes DC series motors are EMPLOYED. At above condition the back emf is greater than supply VOLTAGE hence, it will OPERATE as series generator which will provide energy back to the supply.

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