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PROBLEM 5: Figure shows a screw jack lifting a non- rotating load of 200 kg. The screw jack consists of a single square screw thread with a major diameter of 30 mm and 10 threads per 5 cm. A rotating nut, driven by a leverage arm moves a plain thrust collar with diameter de 50 mm, which in turn lifts and lowers the load. The friction coefficient between the nut and the collar μ -0.25 and the friction coefficient between the screw thread and the nutu 0.2. Determine the screw thread pitch, lead, minor diameter, mean diameter, and lead angle p, 1, dr, dr, λ). Calculate the torque necessary to raise and lower the screw jack. Is this screw jack self-locking? Load- 200 kg Collar Leverage arm Nut Screw thread

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