A misconception which some people may have, is that Force can be represented in a complete way as a number. But in reality, Force is a vector, just like Velocity is a vector, and Speed would be the magnitude, of a Velocity vector.

There could be numerous individual forces acting on a body that has mass. Because they are all vectors, they could be pointing in different or opposing directions, and could even cancel out. But, a vector-summation of all the individual forces acting on a body, will result in the Net Force.

So, a rather dreamy perception that people might have could be:

“There are numerous forces acting on me, and yet I don’t seem to be moving. I’m just sitting in my comfy-chair, with gravity acting on me – Yet I could remain stationary.” Or, ‘My arm could be engaging a wall, with force, and not moving. How is any of this possible?’

Well, if a Scientist computes the vector-sum of all the individual forces acting on a body with known Mass, thus computing the Net Force, then the body will Accelerate with certainty, as a function of this Net Force, and of its own Mass. As long as the Net Force is not a null vector, the result is unconditional.

And of course Velocity is the integral of Acceleration, so that as long as this effect is only short-term, its integral over a longer period of time could be approximately null. Position is the integral of Velocity, and we could still find, that in spite of all the forces I interact with, I haven’t left a certain room for hours.

As to whether the body deforms or not, with these forces acting on it, was something I wrote about in the above posting, but is also something which differs for fundamental particles, from how it is with elastic bodies, that are composed of *many* fundamental particles.

And, If a Scientist knows that additional forces could be acting on a body, but in a way that cancels out, or in a way understood to be negligible, he also doesn’t need to include those in *his* computation of the Net Force.

Dirk