Calculating Work on a Falling Raindrop

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stormypanda
1. The problem statement, all variables, and given/known data
How much work does gravity do on a 1.9-mg raindrop as the drop falls to the ground from a cloud 2500 m above the ground?

Homework Equations


W = FΔx
F = ma

The Attempt at a Solution


I thought this problem would be pretty straightforward since I'd just use the equation for work directly. Δx is given as 2500 m. The mass of the raindrop is 1.9 mg which I converted to 1.9*10^-6 kg. Lastly, the acceleration is due to gravity so it is 9.8 m/s^2.

W = (1.9*10^-6 kg) * (9.8 m/s^2) * (2500 m)
= 0.04655 J

I got 0.04655 J and the site I'm doing these problems on states that my answer is incorrect. I'm not sure where I went wrong?
 
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I agree with your answer and there is no room for round off errors here. Do you know what the correct answer is?
 
kuruman said:
I agree with your answer and there is no room for round off errors here. Do you know what the correct answer is?

Unfortunately I do not. I have 1 attempt left to answer the question correctly and afterwards they'll tell me the correct answer.
 
Somewhere there may be an instruction that g be approximated by 10ms2[/size], perhaps?
 
Your instructor is the final arbiter and can override any scoring made by an algorithm. Take your answer to your instructor and ask what is wrong with it before you try your last attempt.