State four important features of LEM that differ it from normal electric motor.

State four important features of LEM that differ it from normal electric motor. 
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Answer :

Important Features of LEM That Differ it From Normal Electric Motor: 1. In LEM, primary & secondary or stator & rotor have longitudinal arrangement while normal electric motor has circular parts. 2. Air gap between stator & rotor is more in LEM as compared to normal electric motor. 3. Power factor is poor in LEM as compared to normal electric motor. 4. Linear relative magnetic field is produced in LEM and the rotary magnetic field is produced in normal electric motor. 5. Speed is measured in m/sec in LEM and in RPM for normal electric motor. 6. No speed limit for LEM while maximum speed of normal electric motor is 3000 RPM. 7. LEM has Less efficiency as compared to normal electric motor. 8. LEM is ued in high speed levitated system while normal electric motor is used for rotary mechanical output.

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