A 6-pole, 50Hz, 3-φ induction motor is running at 950 r.p.m. and has Cu loss of 5kW. The rotor input is

A 6-pole, 50Hz, 3-φ induction motor is running at 950 r.p.m. and has Cu loss of 5kW. The rotor input is (a) 10 kW (b) 95 kW (c) 100 kW (d) 9.5 kW 
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how can we solve this question .... please suggest solutions

4 Answers

Answer :


A 6 pole, 50Hz, 3-phase Induction Motor is running at 950r.p.m and has cupids of 5kw. The rotor input is 100kw

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Answer :

A 6 pole 50 hz 3 phase induction motor is running at 950 rpm and has rotor copper loss of 5 kw .its rotor input _____ kw 

 
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Answer :

s=(Ns-N)/Ns

 =(1000-950)/1000=0.05.

rotor cu.loss= s*rotor input

we have rotor cu loss=5kW

therefore, rotor input= rotor cu.loss/s

                              =5kW/0.05

                              =100 kW
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Answer :

s=(Ns-N)/Ns

 =(1000-950)/1000=0.05.

rotor cu.loss= s*rotor input

we have rotor cu loss=5kW

therefore, rotor input= rotor cu.loss/s

                              =5kW/0.05

                              =100 kWimage

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