Answer:
Energy of light is [tex]7.62\times 10^{-17} \ Joules[/tex]
Explanation:
Given:
Wavelength [tex](\lambda)=260 \ nm=2.60 \times 10^{-7} m[/tex]
Also we know the speed of light [tex](c) =3 \times 10^8 \ m/s[/tex]
To calculate frequency of light [tex](v)[/tex], divide speed of light[tex](c)[/tex] by Wavelength[tex](\lambda)[/tex]
[tex]v= \frac{3 \times 10^8}{2.60\times 10^{-7}}= 1.15\times 10^{15} \ per \ second[/tex]
Hence frequency is [tex]1.15\times 10^{15} \ per \ second[/tex]
Now, To calculate energy (E), we need to multiply planks's constant [tex](h)[/tex] with the frequency of light [tex](v)[/tex].
Also Plank's Constant [tex](h)[/tex] = [tex]6.626\times 10^{-34}\ J \ s[/tex]
[tex]E = h \times. f = 6.626\times 10^{-34}\ J \ s \times 1.15 \times 10^{15}\ s^{-1} = 7.62 \times 10^{-19} \ J[/tex]
Hence Energy of light is [tex]7.62\times 10^{-19} \ Joules[/tex]
