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SIMPLE MACHINES, , , , In picture (A) a greater distance has, to be moved with less effort, whereas, in picture (B) more effort or force is, needed but the distance to be moved, is less. Work done in both the cases, , , is, however the same., , In hospitals, hotels or public places,, you may see a ramp instead of a, staircase. A ramp is also an inclined, plane. It is shown in the picture on, the left., , , , Screw, , Take out the car jack and change the tyre. The entire task takes just a few, minutes. The car jack makes the work easy because it is a simple machine called, a screw., , A screw is an inclined plane that goes around a cylinder. It has ridges or, threads that change the direction of force applied. The circular motion helps, to move things upward and downward., , A screw holds things together through a longer distance with a stronger grip., A screw is used to lower and raise things and to hold objects together. In a car, jack, when you turn the handle, it raises the platform fixed to it anda heavy, vehicle gets lifted up with less force., , Here are some other examples: