Finding end correction from length vs 1/frequency graph

[Henrymed]

Homework Statement

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I plotted a graph of length against 1/frequency,determined the slope,which was the speed of sound. I got stucked in the (b) part,when asked to deduce the end correction from the graph drawn.[/B]

Homework Equations

The Attempt at a Solution

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I attempted using the formula end correction c,=0.6r to decipher its value experimentally, then compared it with my intercept at the y-axis which was the length(l).The values wvalues didnt correspond,and I knew I was wrong[/B]

 

[DrClaude]

What is the statement of the problem?