Example 3 (a) A steel transmission shaft is 510 mm long and 50 mm external diameter. For part of its length it is bored to a diameter of 25 mm and for the rest to 38 mm diameter. Find the maximum power that may be transmitted at a speed of 210 rev/min if the shear stress is not to exceed 70 MN/m’. (b) If the angle of twist in the length of 25 mm bore is equal to that in the length of 38 mm bore, find the length of the two bored parts. Example 3(a) A steel transmission shaft is 510 mm long and 50 mm external diameter. Forpart of its length it is bored to a diameter of 25 mm and for the rest to 38 mmdiameter. Find the maximum power that may be transmitted at a speed of 210rev/min if the shear stress is not to exceed 70 MN/m?.(b) If the angle of twist in the length of 25 mm bore is equal to that in the length of38 mm bore, find the length of the two bored parts.L1L2510 mmQ38 mm25 mm50 mm

We can consider this case as shafts in series Both parts are subjected to the same torque We know…

(a) A steel transmission shaft is 510 mm long and 50 mm external diameter. For part of its length it is bored to a diameter of 25 mm and for the rest to 38 mm diameter. Find the maximum power that may be transmitted at a speed of 210 rev/min if the shear stress is not to exceed 70 MN/m². (b) If the angle of twist in the length of 25 mm bore is equal to that in the length of 38 mm bore, find the length of the two bored parts. T L1 L2 510 mm Q 38 mm 25 mm Q 50 mm

(a) A steel transmission shaft is 510 mm long and 50 mm external diameter. For part of its length it is bored to a diameter of 25 mm and for the rest to 38 mm diameter. Find the maximum power that may be transmitted at a speed of 210 rev/min if the shear stress is not to exceed 70 MN/m². (b) If the angle of twist in the length of 25 mm bore is equal to that in the length of 38 mm bore, find the length of the two bored parts. T L1 L2 510 mm Q 38 mm 25 mm Q 50 mm

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter3: Torsion

Section: Chapter Questions

Problem 3.7.10P: What is the maximum power that can be delivered by a hollow propeller shaft (outside diameter 50 mm,...

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