The shaft has a diameter of 80 mm. Due to friction at its surface within the hole, it is s...

The shaft has a diameter of 80 mm. Due to friction at its surface within the hole, it is subjected to a variable torque described by the function r = N•m/m. where x is in meters. Determine the minimum torque T0 needed to overcome friction and cause it to twist. Also, determine the absolute maximum stress in the shaft.

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