Pre Lab, how to find uncertainty

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To find the uncertainty of Fave, it is essential to understand how to calculate fractional errors in multiplication and division. The resultant fractional error for a product or quotient can be derived from the uncertainties in the individual measurements. Specifically, the formula for the uncertainty in Fave involves the uncertainties in momentum and time, expressed as ΔFave/Fave = Δ(Δp)/Δp + Δ(Δt)/Δt. This approach allows for accurate determination of ΔFave, which is crucial for completing the prelab assignment. Understanding these concepts is key to resolving the uncertainty calculation.
Habibrobert
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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
 

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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).
 
Hello,

I'm really sorry but I don't understand what you mean?
 
Habibrobert said:
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.
 
The uncertainty in Fave, ΔFave, divided by the value of Fave (what rude man calls the fractional error) is given by

ΔFave/ Fave = 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 ΔFave.
 

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