Question

fill in the blank question
this is law which we use to calculate the intensity of light at depth.
$i_z = i_0e^{-kz}$

Explanation:

The formula $I_z = I_0e^{-\kappa z}$ is the Beer - Lambert law (also known as Beer's law in some contexts) which is used to calculate the intensity of light at a certain depth. It describes the attenuation of light as it passes through a medium.

Answer:

Beer - Lambert