Testing a proportional relationship without a graph

AI Thread Summary
To test the relationship between the speed of water waves (c) and water depth (d) given by c ∝ d^1/2, the equation can be expressed as c = k * d^1/2, where k is a constant. The user is advised to collect data to calculate k and evaluate it twice for accuracy. The discussion highlights that calculating k essentially reflects finding the gradient of a graph that would plot c against d^1/2. If the relationship is proportional, this graph should yield a straight line through the origin. Overall, the approach is confirmed as correct for the practical exam preparation.
GandhiReborn
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Homework Statement



Without a graph, test the suggestion that the speed, c, of the water wave is related to water depth, d, by:

c ∝ d^1/2

No other data is given, this is suppose to be collected by myself but I am revising for a practical exam paper without having the data given. Markscheme just says "suitable data evaluated twice; correct calc.s from correct depths; appropriate concl. drawn)

Homework Equations



As above

The Attempt at a Solution



Surely it's simply if c ∝ d^1/2, ∴ c=kd^1/2
∴ k = c/(d^1/2)

and then I'd use collected data to find k?

Can you please just say yes, or no and help me with what I have done?

Thank you very much! :D
 
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I think you are on the right track.
If you think about it you are actually calculating the gradient of a graph IF you did decide to plot a graph.
Can you see what graph you would plot IF you had been asked for a graphical method?
 
technician said:
I think you are on the right track.
If you think about it you are actually calculating the gradient of a graph IF you did decide to plot a graph.
Can you see what graph you would plot IF you had been asked for a graphical method?

Thank you. :) Yeah I'm pretty sure it'd be c against d^1/2, which if proportional should be a straight line through the origin right?
 
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