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This is not a homework problem. I am very familiar with the case of linear(direction) friction.

[tex]F_{friction}=\mu F_{normal}[/tex] ...(1)

However my question is closer to something like this:

[tex]\tau_{friction}=\beta F_{normal}[/tex] ...(2)

Where [tex]\tau_{friction}[/tex] is a torque

Imagine if a shaft were to be making contact with the floor at its stub. Assuming the normal force that the shaft exerts on the ground is known. Then how much torque would need to be applied around the shafts axis to make it overcome friction and start turning.

Maybe another analogy would be a drill with a flat tip, how much torque would the flat tip need to overcome friction ?

Is equation 2 of the right form ? what name does this effect go by because so far I could only find references to linear friction.

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# Angular friction: torque needed to let a shaft in floor contact spin around its axis

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