MHB Moment of Inertia: Motor, Shaft Speed & Torque Calculation

AI Thread Summary
The discussion focuses on calculating the common speed of rotation, change in angular momentum, change in angular kinetic energy, and the time required for a motor to regain optimum running speed after connecting to a shaft. The motor has a moment of inertia of 15 kgm^2 and operates at 1400 rev/min, while the shaft rotates counter to it at 600 rev/min. Participants are encouraged to share the equations they used and their application methods to identify any errors in their calculations. The thread emphasizes the importance of showing work to facilitate assistance. Overall, the conversation aims to resolve the calculations related to motor and shaft dynamics.
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The rotating parts of a motor have a moment of inertia of 15 kgm^2 and an optimum running speed of 1400 rev/min. When operating the motor is connected at optimum speed , by means of a clutch, to a shaft which has a counter rotation of 600 rev/min. The shaft has a mass of 80 kg and a solid diameter of 1200 mm.

i) Find the common speed of rotation of the two shafts, immediately after slippage has finished.
ii) Determine the change in angular momentum of the motor as the common speed is reached.
iii) Determine the change in angular kinetic energy of the motor as the common speed is reached.
iv) If the motor sends a torque of 220 Nm, find how long it will take for the system to regain optimum running speed for the motor.

I have tried using equations but had no success
 
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Hello and welcome to MHB! :D

Busybee said:
...I have tried using equations but had no success

It would be useful for our helpers to see which equations you used and how you attempted to apply them. Then perhaps it can be found where you may be going astray.
 
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