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

Derive the error expression [tex]\delta v_{}x [/tex] from the equation [tex]v _{x}[/tex]=[tex]\frac{s}{sqrt(\frac{2h}{g})}[/tex]

3. The attempt at a solution

I've derived error expressions before, but I have a history of getting the calculations right and the error equations wrong. So, if possible I'd like to have someone tell me what I am doing wrong (if anything) when I derive this.

For any two numbers divided by one another (2h/g), the error z is:

[tex]\delta[/tex]z=|z|([tex]\frac{\delta x}{|x|} + \frac{\delta y}{|y|}[/tex])

So:

[tex]\delta[/tex]z=|z|([tex]\frac{\delta h}{|h|} + \frac{\delta g}{|g|}[/tex])

At this point intuition tells me that I should just multiply that by two to get the error in 2(h/g), but I think I've done that before and got it wrong.

I have no idea what the error of a square root is. I'm going to guess it's the same as the error in squaring something, so the error in the initial equation would be:

[tex]\delta[/tex]v=|v|([tex]\frac{2 \delta h}{|h|} + \frac{2 \delta g}{|g|} + \frac{\delta s}{|s|}[/tex])

So, am I right? If not, what am I doing wrong? It's fairly crucial to understand these rules, I think, so any help would be wonderful.

Thanks.

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# Homework Help: Help deriving expression for the error in velocity.

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