(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A marble of mass m falls through a fluid and is subject to the drag force F=-Av, where v is the velocity of the marble. The marble will reach a terminal speed given by v=(mg)/A. Use dimensional analysis to estimate how long it will take to reach the terminal speed. (Hint: A characteristic "time" can be constructed from A, g, and m.)

3. The attempt at a solution

The units on A are F/v= (kg/s).

The units on g are m/(s^2).

The units on m are kg.

However, g is the only value with meters, so I don't know how I'm supposed to combine them and get time, unless it's just m/A, but then why did the book give a hint about using g? Thanks for the help.

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# Homework Help: Drag (Unit Analysis)

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