Simple Machines
Today we are going to investigate machines. Machines are tools that make work easier. Men and women have been using six basic machines for thousands of years. These six types are known as simple machines.
Have you ever played on a seesaw or used a shovel,crowbar, or nutcracker? If you have, you have used a simple machine called a lever! A lever is made up of two parts: a stiff bar that moves and a part called a fulcrum that does not move. A lever is used to push, pull, or lift things.
Another simple machine is the inclined plane. An inclined plane is a flat surface that is slanted so that one end is higher than the other. It helps move heavy objects up or down. A ramp is a type of inclined plane. People in wheelchairs use ramps instead of steps. With the help of a ramp, disabled people can easily roll from the street to the sidewalk and from the sidewalk to the front door of a building. I am sure that if you check out the front of your school building, you will find one or more ramps!
Another kind of simple machine is the screw. It is an inclined plane wrapped around a cone or cylinder. Screws are often used to hold things together. If you have ever opened the lid of a jar or tightened a screw on your bike or classroom bookcase, you have used this simple machine!
SOL 3.2, Part 1 Force, Motion & Energy
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Simple Machines
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If you have ever used a knife or ax, you have used another simple machine: the wedge! A wedge is a simple machine that cuts or splits things apart. It is wide at one end and pointed at the other.
Did you know that a door knob is a simple machine? It’s called a wheel and axle! This type of machine is made of a rod connected to a wheel. A wheel and axle makes it easier for you to move or turn things. Some other examples include bicycle wheels and roller skates. A screwdriver is also an example of a wheel and axle, but where is the wheel and axle? I bet you can figure it out!
Does your school have a flagpole out front? A flagpole is an example of another simple machine called a pulley! A pulley is made of a wheel that has a rope wrapped around it. It makes lifting heavy objects easier. A mini-blind is another example of a pulley you have probably used at home or in your classroom.