The Crane works by bringing heavy material to a designated area.It works by 3 simple machines.Those 3 simple machines are a lever, pulley and a wheel and axle but just in bigger pieces. The 2 that are going to be explained is the wheel and axle and the pulley which are the ones that pick up and drop off the load.I found out information on a youtube video to see a visual representation and read about it on an internet page that broke into pieces explaining every different simple machine on the crane.In my opinion I saw it really cool because as you see a crane in the street and see it pick up real heavy material how can it just pick it up with a single pulley an be safe.
The lever is what makes the pulley come down and pick up the load so it will get longer as the pulley comes down.
The pulley is a fixed pulley with a rope and a wheel and axle.It changes the direction of force and the rope gets lowered as it is getting ready to lift load then the rope comes up as it is lifting the load.
https://prezi.com/8vhlkm7vi2hs/simple-machine-crane/
This is a good example of the way simple machines can be combined to make more complicated machines, but I think the prezi has a slight error in it. The images and the text don’t quite match. The text says that the load arm is shorter than the effort arm of the lever (which might be true of some cranes), but the images in presentation shows a lever which can change length. This means that the ratio between the load arm and the effort arm will change depending on the use of the crane.