|Inclined Plane | Wedge | Screw | Lever | Wheel and Axle | Pulley||Back to Step 1|
Basically, a screw is like the ramp and the width of the thread is like the angle of an inclined plane. The wider the thread of a screw, the harder it is to turn it. And here's the trade-off: If you've ever had to put in a screw with really narrow threads, you've probably found that you have to turn it a really long time to get it to go anywhere. Just like in a ramp, the easier the effort, the longer the distance you have to move something!