Calculate terminal velocity when given cross sectional area

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Tatortotts
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Homework Statement


Two packages are dropped from an airplane. A parachute can increase the cross sectional area of each packages by a factor of 31. The parachute on package 1 fails to open, and the terminal speed of package 1 is 10 m/s. The parachute on package 2 opens.

What is the terminal speed of package 2 in m/s?

Homework Equations


Unsure, considering the problem gave very few numbers to work with.
R = ½CρAv2

The Attempt at a Solution


I figured since A (cross sectional area) is inversely proportional to vterminal2, that you would square package 1's vterminal (to get 100 m/s) and then divide by 31. I haven't submitted my answer yet so I'm not sure if it's right.
 
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Tatortotts said:
I figured since A (cross sectional area) is inversely proportional to vterminal2, that you would square package 1's vterminal (to get 100 m/s) and then divide by 31.
Have you left out a final step?
 
haruspex said:
Have you left out a final step?
Well, vterminal2 is proportional to 1/A, so 102 = 1/(A*31)
Solving for A I then get 1/3100 m/s, which seems a little ridiculous.
I submitted my answer (from my original solution--3.2 m/s) and it was wrong, so I know I'm missing something. I just can't seem to figure out what.
 
Tatortotts said:
Well, vterminal2 is proportional to 1/A, so 102 = 1/(A*31)
Solving for A I then get 1/3100 m/s, which seems a little ridiculous.
I submitted my answer (from my original solution--3.2 m/s) and it was wrong, so I know I'm missing something. I just can't seem to figure out what.
Here's a hint. The square of 10m/s is not 100m/s. What is it?
 
haruspex said:
Here's a hint. The square of 10m/s is not 100m/s. What is it?
Would it then be 100m2/s2? So I should take the square root of my answer?
 
Tatortotts said:
Would it then be 100m2/s2? So I should take the square root of my answer?
Yes.
 
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haruspex said:
Yes.
Thank you so much! I don't know why I decided to neglect units for that problem.