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What is it?
The work formula in physics goes like this:
Translation: The work done (W) is equal to the applied force (F) multiplied by the distance (D) the object travels. Give me an example!
Have you ever tried to lift something heavy, like a big book? Let's apply The Work Formula to see which situation involves doing work: (1) Holding a book in the same place above your head for 10 hours, or (2) Lifting the same book one inch off the floor. In situation #1, you apply a force to the bottom of the book which is precisely equal to the weight of the book, but in the opposite direction. So the forces cancel each other (the total or net force is zero) and the book doesn't move, creating a distance of zero:
Remember, when you multiply anything by zero, you get zero. So if an object doesn't move, no work is done on it. On the other hand, when you move an object (such as lifting a book one inch off the floor), you have a change in distance, which means that work is actually being done in that situation. |
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