# Error calculation for µ in standing wave experiment

## Homework Statement

I experimented with standing waves on an oscillating string, and I was asked to calculate the absolute error of µ (linear mass per unit length). I don't know how to calculate it, so please help me.
I loaded 100g, 200g and 300g on the string. Below are tabulated data of the experiment.

## Homework Equations

I know the basics of uncertainties, but in here it's kinda complicated as I don't know how to calculate the tension or speed error. I know this formula: where c= speed, FT= tension and µ = linear mass per unit length

making µ the subject: ## The Attempt at a Solution

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So the calculated tension for the 3 sets of masses are:
100g = 9.81*0.1=0.981
200g= 9.81*0.2=1.962
300g= 9.81*0.3=2.943

Speed:
100g= 39 m/s
200g= 54 m/s
300g= 72 m/s

µ values:
100g -> 0.981/39^2 = 644.9*10^-6 kg/m
200g -> 1.962/54^2 = 672*10^-6 kg/m
300g -> 567.7*10^-6 kg/m

Do i like average the tension and speed values and subtract the max and min number

So if i do that then:

average of tension = 1.962
2.943-0.981=1.962 <- this is the uncertainty?

average of c^2:
• averaging -> 39+54+72/3 =55
• squaring -> 55^2 = 3025
72-39= 33
72^2-39^2=3663

This seems very wrong i don't really know what I'm doing.   #### Attachments

• ephphatha16

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