What We Mean by Force and Pressure


  • B. A. R. Ladnuop


A popular word is frequently so popular that it is received with open arms, or rather with open mouth and open ears, when really it should not be present at all in the company of those words with which it is associated on that particular occasion to form a sentence. The scientist, even when talking lightly and brightly (and even flippantly), should be very careful of the words he employs; so he likes to have all the words he intends to use regularly for scientific purposes carefully defined to have only one meaning. This article is about what we may popularly term "pushes" and "pulls" - both really quite good words, because we use them so frequently that we know what to expect when we push a thing or pull it. If you simply pull a free object, you expect generally that it will move towards you; and if you push it, you expect it to move away from you. Scientists prefer to use the word "force" when dealing with this action. We apply a force to a body, and, if the body be free to move, it will move in the direction of the force.