(6) A double square-threaded power screw transmits 1,800in-lb of torque and raises a machine head; the head is guided by linear slides with anti-friction bearings, and thus no appreciable friction is involved. If the coefficient of friction for the threads is 0.1, find: (a) the load that can be raised if the screw has 2 threads/in and an outside diameter of 21/in; (b) if a 4000-lb load is to be lowered, what torque must the screw transmit? (c) if the power screw of rotates 10 rpm, what is the linear speed of the driven head in feet per minute?

(6) A double square-threaded power screw transmits 1,800in-lb of torque and raises a machine head; the head is guided by linear slides with anti-friction bearings, and thus no appreciable friction is involved. If the coefficient of friction for the threads is 0.1, find: (a) the load that can be raised if the screw has 2 threads/in and an outside diameter of 21/in; (b) if a 4000-lb load is to be lowered, what torque must the screw transmit? (c) if the power screw of rotates 10 rpm, what is the linear speed of the driven head in feet per minute?

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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(6) A double square-threaded power screw transmits 1,800in-lb of torque and raises a machine head; the head is guided by linear slides with anti-friction bearings, and thus no appreciable friction is involved. If the coefficient of friction for the threads is 0.1, find: (a) the load that can be raised if the screw has 2 threads/in and an outside diameter of 2½in; (b) if a 4000-lb load is to be lowered, what torque must the screw transmit? (c) if the power screw of rotates 10 rpm, what is the linear speed of the driven head in feet per minute?
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