Question

A tank is filled with a liquid to a height of \(12.5\,\text{m}\). The apparent depth of a needle lying at the bottom of the tank is measured to be \(9.0\,\text{m}\). Calculate the speed of light in the liquid.

Hint:

Remember the useful relation: \[ \mu=\frac{\text{Real Depth}}{\text{Apparent Depth}} \] and \[ v=\frac{c}{\mu}. \] Whenever apparent depth is given, first calculate the refractive index and then determine the speed of light in the medium.

Answer 1