Question

give the ratio of velocity of light ray of wavelength 4000A⁰ AND 8000A⁰

Answer 1

Dear Student,

$$\begin{gathered} \mathrm{Wavelength}\mathrm{of}1\mathrm{st},{\mathrm{\lambda }}_1=4000\stackrel{0}{\mathrm{A}} \\ \mathrm{Wavelength}\mathrm{of}2\mathrm{nd},{\mathrm{\lambda }}_2=8000\stackrel{0}{\mathrm{A}} \\ \mathrm{We}\mathrm{know}\mathrm{that}, \\ \mathrm{c}=\mathrm{\lambda \nu } \\ \frac{{\mathrm{c}}_1}{{\mathrm{c}}_2}=\frac{{\mathrm{\nu \lambda }}_1}{{\mathrm{\nu \lambda }}_2} \\ \frac{{\mathrm{c}}_1}{{\mathrm{c}}_2}=\frac{{\mathrm{\lambda }}_1}{{\mathrm{\lambda }}_2} \\ \frac{{\mathrm{c}}_1}{{\mathrm{c}}_2}=\frac{4000}{8000} \\ \frac{{\mathrm{c}}_1}{{\mathrm{c}}_2}=\frac{1}{2} \end{gathered}$$