By Shelby

What is a machine?

A machine is any device that helps people do work. A machine does not decrease the amount of work that is done. Instead, a machine changes the way in which work is done. It makes it easier. As an example you have to lift a heavy box, you can use a ramp to make the work easier. Moving the box up a ramp, which is a machine that helps you do the work by reducing the force you need to lift the box.

How are machines powered?

Machines are powered by different types of energy. Some use electrical energy, such as computers. Mechanical machines, such as a rake, use mechanical energy. Often mechanical energy is supplied by the person using the machine.

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How do machines work by changing the size of the force needed?

Input force is the force exerted on a machine. Output force is the force that a machine exerts on an object. Like if you take a rake and start raking The work you put into the rake is the same as the work he gets out of the rake. However, the force you apply is greater than the force the rake can apply to the leaves. The output force is less than the input force, but it acts over a longer distance.

How efficient are machines?

A hammer is used to pound in nails. It can also be used to pry nails out of wood. When used to pry nails, a hammer is a machine called a lever. Like all machines, the hammer is not 100 percent efficient.

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Is a robot a machine?

A robot is a machine that works automatically or by remote control. Robots are used to do jobs in places that are dangerous for humans to do. Robots do some repetitive work better than humans, because they don’t get tired or bored.

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