Machine - Defnition

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What is machine?
A machine is any device which reduces human effort by using mechanical parts and concepts.

In what are the ways we use machines? Give examples too.
1.    Machines are used to transform energy- Generator
2.    Machines are used to transfer energy from one place to other – Crank shaft
3.    Machines are used to multiply the energy- Pulley
4.   Machines can be used to multiply speed- Bicycle
5.    Machines can be used to change the direction of a force – Flag hoist

What are the simple machines available?
1.    Lever
2.    Pulley
3.    wheel and axle
4.    inclined plane
5.    Screw
6.   Gear

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