Light Falling to a Black Surface is Converted to Which Energy Form?

Most recent answer: 01/27/2015

Q:
According to law of conservation of energy, energy is transferred from one form to another. Then the light energy falling to a black surface is transferred to which energy form?
- Varun s prakash (age 16)
Mannar ,Kerala ,India
A:

That is a really good point. Black just absorbs more (wavelengths), so let`s illustrate this for you. On a shiny summer day you stay under the sunlight say for an hour, what do you observe? First of all, you will feel quite warm, so mostly heat. But depending on the surface there could be side reactions, for instance your T-shirt's colour will gradually fade away due to a light induced chemical reaction. If you are wearing a watch with phosphorescent backscreen, then the light will also be exciting those molecules. In fact, it could even rip off some electrons as occurs in the leaves of the grass on which you are lying during photosynthesis.

Tunc


(published on 01/27/2015)