28 Questioning the Universe: Concepts in Physics
This is a deceptively simple-looking relation, and also misleading as written.
Usually when writing an equation, the implication is that the quantities on the right-
hand side cause or determine the quantity on the left. For instance, in Equation 4.2,
the weight of an object is determined by its mass and the other quantities in the
parentheses. So, the way Equation 4.3 is written implies that acceleration causes
force, but just the opposite is true. It is a force applied on an object that causes the
object to accelerate. Thus, in order to convey the correct meaning, we should write
Newton’s second law as
a = F/m (4.4)
In addition, F can be easily misinterpreted. For instance, I assume you are ...