Calculating Drag Force Constant in a Simple Physics Problem

AI Thread Summary
The discussion centers around calculating the drag force constant, C, for a 0.142 kg ball with a terminal speed of 42.5 m/s, where the drag force is defined as R=CV^2. The original poster expresses confusion about the variable R, mistakenly thinking it might represent mass, but later clarifies that R is indeed a drag force. Participants emphasize the importance of understanding the relationship between drag force and gravity in this context. The conversation highlights the need for clarity in physics problems, particularly when certain formulas are not covered in textbooks. Overall, the thread provides a helpful resolution to the initial confusion about the drag force equation.
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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?
 
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Use F = ma = drag force, with the left side determined by gravity's force, and the right side given by the drag force.

Don't worry about it being ridiculously easy. If that's your worst problem this semester you done good.

Carl
 
The question tells you "a drag force of R=..."

That is, R is a force - a drag force.
 
Okay, I see. Thanks for the assistance.
 

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