$\lambda_1$ factor in context of buckling

Question

I'm studying this text about buckling.

There a factor called $\lambda_1$ is defined:

$$\lambda_1=\pi \sqrt{\frac{E}{f_y}}=93.9\sqrt{\frac{235}{f_y}}$$

But how was that last step made? Where did that factor of 93.9 come from? Usually we take the elastic modulus of structural steel as around 200GPa, so how is there 235 under the square root? I feel like there is some step missing.

Answer 1

Edit

I have changed the units to MPa, basically cranking their numbers back to see what unit they have used for E.

Without looking at your source, it makes sense if they are using the unit of MPa.

$E=210.000MPa$

then:

$$\lambda_1=\pi\sqrt\frac{210,000}{F_y}=\sqrt\frac{893.617*235}{F_y}$$

$\lambda_1=93.91\sqrt\frac{235}{F_y}$