Which is easier? Lifting a piano ten feet up in the air? Or pushing it up a ramp until it’s ten feet from the ground?
Most people would say pushing it up a ramp.
Ramps are also called inclined planes. They are one type of simple machine. Simple machines make work easier. Levers, wheels, screws, wedges, and pulleys are other kinds of simple machines. Then there are compound, or complex, machines. These combine more than one simple machine. Some examples are computers, cranes, and cars.
Simple machines are so common, you may not see how much you need them. But without them, you’d find it hard to get through a day. It might even be impossible!
