Pre Lab, how to find uncertainty

[Habibrobert]

Hello,

I have been stuck on this prelab all day.I have finished all the questions except for the last one, where it asks you to find the uncertainty (or standard deviation) of Fave. I have tried every resource and nothing has helped so far. Any help would be great!

Thanks

 

[rude man]

When you multiply or divide two numbers with fractional error f1 and f2 respectively, what is the resultant fractional error of the product or quotient? (Assuming normal error distributions).

 

[Habibrobert]

Hello,

I'm really sorry but I don't understand what you mean?

 

[rude man]

Hello,

I'm really sorry but I don't understand what you mean?

Like, (x +/-Δx) * (y +/-Δy) gives (xy +/- what)?

Annd division is just 1/multiplication so it follows the same rule.

 

[Basic_Physics]

The uncertainty in F_ave, ΔF_ave, divided by the value of F_ave (what rude man calls the fractional error) is given by

ΔF_ave/ F_ave = Δ(Δp)/Δp + Δ(Δt)/Δt

where Δ(Δp) is the uncertainty in the change of the momentum and Δ(Δt) is the uncertainty in the time interval - see the summary at the end of
http://www.physics.mcmaster.ca/undergrad/Uncertainties/U.htm

What you need to calculate is then ΔF_ave.