Q8DQ - University Physics with Modern Physics

Question

If you look up from underneath toward the surface of the water in your aquarium, you may see an upside-down reflection of your pet fish in the surface of the water. Explain how this can happen.

Step-by-Step Solution

Answer

This happen due to total internal reflection.

Step 1: Definition of Total internal reflection

A phenomenon of reflection of ray back to the same medium when passing from denser medium to rarer medium in a such away that angle of incidence greater than its critical angle is called Total Internal Reflection.

Step 2: Upside-down reflection of fish in aquarium due to total internal reflection

When one look into the aquarium from underneath, the ray travels in the water and the incident angle equals the critical angle so the total internal reflection occurs and the ray that comes from the fish looks like one see it in a mirror.

Hence, there is upside-down reflection of pet fish in the surface of the water.