First read Mechanical advantage.

Remember that the amount of work done by the effort is exactly the work done by the load. In the example on the left, the distance travelled by the lever is greater than the distance travelled by the load. The load is lifted up very slowly.

Work done by load = work done by effort
Work = force applied X distance travelled
Force X distance = Force X distance

A car jack is used to lift a heavy load. The lever attached to gear "A" travels through a distance of 4.45m when a force of 34N is applied. The load is lifted to a height of 0.50m. Assuming no friction, what is the maximum load that can be lifted by the 34N force?

What type of gear system is this?

Solution

Look at the drill on the right. The handle rotates through a distance of 32cm. A drill bit attached to the end of the drill rotates a distance of 4 cm.What force is exerted on the drill bit if a force of 40N was applied to the handle?

*Hint
Work done by handle = work done by drill bit.
Work = force applied X distance travelled.