Question

Derive an expression for velocity ratio of the simple screw jack

Answer 1

Screw jack will be employed for lifting heavy loads which are usually can be loaded upon it. They will be applied for the power with the level handle

So we assume that l = Radius of the effort wheel

P = effort involved to lift the load,

p = pitch of the screw,

W = Load lifted and T = Number of teeth on the worm wheel.

The distance moved through the effort in one revolution for the wheel  is= 2πl

If the worm will be single threaded then the worm wheel move through 1/T revolution.

Therefore the distance has moved by the load = p/T V.R.

= 2πl/ p/T M.A.

= W/P Efficiency

= M.A. / V.R

Answer 2

Answer:

To derive an expression for velocity ratio and a simple screw jack, you will have to check the answer below- The answer is M.A. / V.R.

Screw jacks are used to lift heavier loads upon it.

Let us assume that I is the radius level of the effort wheel, P is the effort involved to lift the load and P is the pitch of the screw.