## College Physics (7th Edition)

a). $25^{\circ}$ b). $1.97\times10^{8}m/s$ c). $362nm$
a). By Snell's law, $n_{a} sin(i) = n_{g} sin (r)$ Thus, $sin(r) = \frac{sin40^{\circ}}{1.52}$ Thus, $r=25^{\circ}$ b). $velocity=\frac{c}{index}=\frac{3\times10^{8}}{1.52}=1.97\times10^{8}m/s$ c). $Wavelength _{glass}= \frac{Wavelength_{air}}{index_{glass}}=\frac{550nm}{1.52}=362nm$