work

 Work

    Did you know that you work every time you cause something, including yourself, to move or change position? Scientists think of work as the use of force to move an object. Playing tag is actually work, since you are moving your body. The amount of work that is done depends on how much force is used and how far the object is moved.

   Think about trying to push a wall again. Even if you pushed as hard as you could and used great force, you would not move that wall. Since work is done only when force makes something move, no work would be done.

   Is there another way to move that wall? Maybe you are thinking that a machine could be used to move the wall. You are right to think of using a machine. A machine would be able to push the wall with more force.

Vocabulary:

position            :        chức vụ

amount             :        số lượng

depends         :      phụ thuộc

force                 :        từ

machine            :        cỗ máy

able                   :        có thể