Answer
490 nm
610 nm
640 nm
670 nm
Work Step by Step
The slit separation is $d=\frac{1}{9800}cm$. Use equation 24–4 to find the wavelength for first order lines.
$$d sin \theta = m \lambda $$
$$\lambda=\frac{d sin \theta}{m}$$
$$\lambda=\frac{(\frac{1}{9800}cm)(sin 28.8^{\circ})}{1}$$
$$=4.92\times10^{-5}cm\approx490nm$$
Repeat for the next angle.
$$\lambda=\frac{(\frac{1}{9800}cm)(sin 36.7^{\circ})}{1}$$
$$=6.10\times10^{-5}cm=610nm$$
Repeat for the next angle.
$$\lambda=\frac{(\frac{1}{9800}cm)(sin 38.6^{\circ})}{1}$$
$$=6.37\times10^{-5}cm\approx640nm$$
Repeat for the next angle.
$$\lambda=\frac{(\frac{1}{9800}cm)(sin 41.2^{\circ})}{1}$$
$$=6.72\times10^{-5}cm\approx670nm$$
