The given points are:
\[
A(5\cos 0, 0) = (5,0) \quad \text{and} \quad B(0, 5\sin 0) = (0,5).
\]
Using the distance formula:
\[
d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2}
\]
\[
= \sqrt{(0 - 5)^2 + (5 - 0)^2}
\]
\[
= \sqrt{(-5)^2 + (5)^2}
\]
\[
= \sqrt{25 + 25} = \sqrt{50} \approx 5.
\]