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  • Simple Machines in Our Daily Lives

  • What are simple machines?

  • They are inventions that that people thought of thousands of years ago

  • to make their lives easier.

  • Did you know that we use those same simple machines every day in our modern world?

  • Let's look at some of our modern inventions

  • that are actually simple machines!

  • The Lever

  • There are many modern inventions that are levers.

  • A hammer is a lever that you use to pull out nails.

  • A bottle opener is a levertoo.

  • You use it to take off bottle caps.

  • When you ride on a seesaw in the playgroundyou're using a lever.

  • The board rests on a point in the middle.

  • When you push down on  one end f the board, the other end goes up.

  • The Ramp

  • A ramp is a flat surface that has one high end and one low end,

  • making it easier for us to climb.

  • Do you know that you use a ramp at school or at home every day?

  • You use the stairs!

  • People in wheelchairs and cars also use ramps.

  • Of course, there are many ramps  in nature.

  • They are called hills and mountains!

  • The Wedge

  • A wedge is like two ramps put together, so that one edge is sharp.

  • You might ask, "When would I need a wedge?"

  • If you enjoy eating, you need one almost every day!

  • A knife andfork are both wedges, which cut into food.

  • So is an axe, which people use for chopping wood.

  • We use this sharp edge to push things apart.

  • The Screw

  • A screw is a ramp that winds around and around in a circle.

  • When you turn the screw, it moves and pushes against something else.

  • If you use light bulbs, you are usingscrew to put them tightly into lamps.

  • Jar lids are also screws.

  • Without the screw, it would be  very difficult to hold things together tightly.

  • The Wheel and Axle

  • A wheel and axle is a very simple machine,

  • but important for many modern inventions.

  • An axle goes into the middle of a wheel, making it easy to turn.

  • We use the wheel and axle on many of  our vehicles: cars, trucks, and bicycles.

  • Can you imagine a world without clocks, computers, or even doorknobs?

  • They all use the wheel and axle.

Simple Machines in Our Daily Lives

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B2 中高級 美國腔

Oxford Discover 3 Unit 13 Simple Machines in our daily lives(Oxford Discover 3 Unit 13 Read along Simple Machines in our daily lives 2)

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    Ben 發佈於 2024 年 04 月 02 日
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