Why does heat make that wavy look on pavement??

Question

Why does heat make that wavy look on pavement??

Answer 1

light refraction.  lgiht waves normally travel in plane, but divert out of the plane as the medium (the "stuff" the light is passing through) is modified.  The air is hotter immediately above the pavement, so light is bent as it passes through it.  SInce the heat is not uniform, the bending of the light is not uniform, and you receive a distorted image.

Answer 2

Moisture from the pavement that has been heated makes gas that makes the pavement look wavy.

Answer 3

Photons travel at the speed of light only in a perfect vacuum but are often bent when passing through denser materials.  Look at a long pencil with half of it submerged and it looks bent.  Because the air above a hot road surface is heated unevenly (especially when viewed at a slight angle above the road from inside a car), the average density of the air along a relatively long path from road to eye may vary enough to bend light differently from numerous points on the pavement.  Likely black asphalt works better than light concrete in absorbing heat to cause that wavy look.  If you look straight down at the hot road, the path is so short the wavy affect is gone.