Question

Determine power absorbed per $m^2$.

• A. $8\times {10}^{-9}W{m}^{-2}$
• B. $7\times {10}^{-9}W{m}^{-2}$
• C. $8\times {10}^{9}W{m}^{-2}$
• D. $9.9\times {10}^{-9}W{m}^{-2}$

Answer 1

The correct option is A $8\times {10}^{-9}W{m}^{-2}$

Intensity of light falling $I_o={10}^{-8}W/m^2$
Wavelength of light $\lambda =365\times {10}^{-9}m$
Absorption coefficient $a=0.8$
Thus intensity of light absorbed $I=a{I}_o=0.8\times {10}^{-8}=8\times {10}^{-9}W/m^2$