Over 2,000 years ago, Archimedes was obsessed with this simple question--
How can I lift a 100 kg mass to a height of 1 m?
Okay so this might not have been exactly how we phrase the question, but this captures the essence
of what Archimedes was thinking when he invented many of these simple machines.
Naively, we might think the only way to answer these question of
how to get this, let's say 100 kg rock unto this 1 m table.
It is well, to pick it up and put it on the table.
Archimedes, however, realized there's better way to solve this problem.
One way is to use an incline plane and we analyzed the incline plane
a little bit in the previous problem set.
When we use an incline plane, we reduced the force we have to push with the one in expense.
We have to push over longer distance before we have to lift 1 m
but now we have to push a distance that's greater than 1 m.
Another option is to use a system of pulleys.
Pulleys actually have the same trade off that incline planes do.
We may not have to pull quite as hard but we'll have to pull over a greater distance.
Once again we see this force and distance trade off popping up.
Another simple machine that can help us out is the lever.
If we use the lever, we can exert a smaller force than we would have to if we we're just picking it up
but once again we'll have to exert it over a greater distance just to lift this rock 1 m.
This is very interesting, let's dig dipper into some of this simple machines
and see if can quantify what's going on.
