Dynamics of Motor-Load Combination (Cont.)

• The different loads connected to the motor will have different speed, to select the motor it is desirable to refer all mechanical quantities like load torque, inertia etc at one single axis, mostly the output shaft of the motor.
  
  
• Principle of energy conservation is used.
  
  
• Let ?M and ?L be the motor and load speeds respectively,
  
  
• Equating power,