A single - threaded 30 mm diameter power screw has a pitch of 6 mm. The vertical load on the screw reaches 8 kN. The coefficients of friction are 0.1 for the threads and 0.12 for the collar. The collar frictional diameter is 50 mm. (i) Find the torque required to raise and lower the load. [3] (ii) Determine the overall efficiency of the power screw. [3] (iii) Find the torsional and compressive body stresses. [3]

A single - threaded 30 mm diameter power screw has a pitch of 6 mm. The vertical load on the screw reaches 8 kN. The coefficients of friction are 0.1 for the threads and 0.12 for the collar. The collar frictional diameter is 50 mm. (i) Find the torque required to raise and lower the load. [3] (ii) Determine the overall efficiency of the power screw. [3] (iii) Find the torsional and compressive body stresses. [3]

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter8: Potential Energy And Conservation Of Energy

Section: Chapter Questions

Problem 8.10CYU: Check Your Understanding Repeat Example 8.10 when the particle’s mechanical energy is +0.25 J.

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