The first part of a pretty involved, 8 part question on modelling drag force states: "A 0.142 kg ball has a terminal speed of 42.5 m/s. If a ball experiences a drag force of R=CV^2, what is the value of the constant, C? I know this is a ridiculusly easy problem, but our text doesn't cover the formula for drag force at all, and I'm not sure what the R variable is. I mean, I know that v is velocity, so you'd think by elimination, R must be somehow represent mass, but the answer that produces isn't accepted by the homework system. So, who wants to tell me what R is, and possibly make fun of my ignorance a little too? Any takers?