Question

Water absorbs light. As depth increases, intensity of light decreases linearly. At $13.5$ feet, water absorbs $50$ percent of light which strikes the surface. At what depth would the light at noon be reduced by $\frac{1}{3,00,000}$ of the noon light.

Answer 1

Given that,

According to inverse proportionality, the depth at which light intensity become $\frac{1}{300000}$

Of the light of the noon is given by,

Depth of sea=$300000\times \frac{13.5}{2}=\frac{4050000}{2}=2025000$feet.

Hence the answer.