A real correlation and a nonsense one

Before you are told which is which

Two charts, r = 0.937 and r = 0.918. Write down which one you think is physics, and why.

Do not change this once you have written it. Being wrong here is the point — it is what makes the next part mean something.

Which of these two chose its axes to make a point?
How much weaker would the second have to be before you stopped believing it -- and is that a number or a feeling?
Somebody shows you r = 0.9 for a claim you already agree with. What do you ask them?

How I know

Point at the chart. Which part of it makes your answer true?

After the reveal

Look at what you wrote at the top. Did it survive? If it did not, what did you assume that turned out not to be true?