If I would draw a right triangle with legs of length 1 centimeter with a ruler then its hypotenuse should be equal to $\sqrt{2}$ which is an irrational number - therefore its decimal representation, which is the limit of the sequence $\underset{n\to \mathrm{\infty}}{lim}\sum _{i=0}^{\mathrm{\infty}}\frac{{a}_{i}}{{10}^{i}}$, has infinitely many numbers after the interger part of$\sqrt{2}$.

What exactly can the ruler measure when drawing such a triangle, considering the fact that we draw irrational number (which by definition is infinitely long)?

What exactly can the ruler measure when drawing such a triangle, considering the fact that we draw irrational number (which by definition is infinitely long)?