Shaft Power Equation
The power of a shaft is its ability to rotate a load at a certain speed. The faster the shaft rotates, the more power it has. To calculate the power of a shaft, you need to multiply the torque of the shaft by its angular velocity.
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Average Shaft Power
The average power is calculated by applying average values for the shaft power equation.
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Shaft Bending Stress
The largest alternating and mean bending stresses are at the outside surface.
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Shaft Torsional Stress
Shaft torsional stress is derived from the shaft bending stress.
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Torsion Equation of a Shaft
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Torque and the Diameter Equation for a Solid Shaft
To calculate the diameter of the shaft we can, derive a equation from the torsion equation. And the equation below also can be used for calculating the bearable twisting moment of a give shaft.
![](https://mechcollege.com/wp-content/uploads/2021/06/image-62.png)
Torque and the Diameter Equation for a Hollow Shaft
Even we most commonly use solid shafts, in some cases, we have to use hollow shaft. Since the polar moment inertia of a hallow shaft is kind of different,
![](https://mechcollege.com/wp-content/uploads/2021/06/image-64.png)