Screw jack.
How can a screw lift a heavy load?
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How can a screw lift a heavy load?
Fit the components, then test the mechanism.
A full turn advances the nut by the screw lead. A smaller lead reduces raising torque while requiring more turns for the same lift. Friction makes the input work larger than the gained potential energy.
Direct rotating screw, quasistatic raising, constant efficiency. No self-locking or breakaway-torque claim.
Raise 200 kg by 40 mm using less than 8 N·m.
Compare lift, turns and raising torque.