Wheel and Axle.
What other way have we for raising weights?
We have the wheel and axle, as is shown in [Fig. 53].
Fig. 53.
What is the wheel and axle?
The wheel and axle is only another form of the lever.
Where is the power applied?
The power is applied to the rope which passes around the wheel.
Where is the weight?
The weight is the bucket attached to the rope which passes around the axle.
Where is the fulcrum?
The fulcrum is the frame on which the ends of the axle rest.
Is the power applied to the wheel equal to the weight to be raised?
No; the power is always less than the weight to be raised.
Upon what do the power and the weight depend?
They depend upon the size of the wheel and the axle.
When the diameter of the wheel is ten times the diameter of the axle, how much will one pound raise?
One pound applied to the wheel, will then raise ten pounds on the axle.
What is a windlass?
A windlass is another form of the wheel and axle, as is shown in [Fig. 54].
Fig. 54.
What is used in a windlass in place of the wheel?
A crank or handle is used in place of the wheel.
Does the crank take the place of the wheel?
Yes; when the crank is turned, it forms a circle the same as the outside of the wheel.
To what use is the windlass often applied?
The windlass is often used to draw water from wells.