# Find mass per unit length of a string graphically

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1. Sep 27, 2016

### jbumbes

1. The problem statement, all variables and given/known data
frequency, Tension, mass, mode of vibration

2. Relevant equations
v = sqrt(T/μ)

3. The attempt at a solution
length of string is 2.14m
weight .00247kg
mass per unit length (μ) .00089

However, I need to confirm this graphically. I solved for mass per unit length
μ = T/V^2
or sqrt(μ) = sqrt(T)/v
however, I have already graphed this and the slope is 33.5. With velocity on the y-axis and sqrt(T) on the x which seems way too off. Basically I have to find the experimental μ graphically.

2. Sep 27, 2016

### andrevdh

That gives an error of about 23% then - the difference between the experimental and real value for linear density?
You did take the wavelength to be the twice the distance between two adjacent nodes?
Is the string running straight from the top of the pulley to the other end where it is fixed or tied to the vibrator?

3. Sep 27, 2016

### BvU

This in itself is strange. Can you explain how you calculated this ?

4. Sep 27, 2016

### andrevdh

That is the experimentally determined value, which then gives a 23% difference between the two.

5. Sep 27, 2016

### BvU

I mean that 2.47/2.14 is not 0.89 but 1.15 gram/meter

6. Sep 28, 2016

### andrevdh

The 0.00089 value is from his gradient