Answer
$8.2\times10^{-4}m$
Work Step by Step
This is nearly identical to Example 25–11. Solve for the separation s, using 450 nm for the wavelength of blue light.
$$s=\mathcal{l} \theta=\mathcal{l}\frac{1.22 \lambda}{D}$$
$$s= (15m)\frac{1.22(450\times10^{-9}m)}{0.010m}=8.2\times10^{-4}m $$
