If you are standing in the penumbra, you will experience a partial eclipse, with the light from the sun dimmer than is typical for that time of day. When a visible light photon hits an object, the energy of that photon can be absorbed by an electron and that photon no longer exists. However, the electron also could reemit photons of lower energy. These lower energy photons are called infrared photons and this form of radiation is not seen by our eyes, but is felt as heat. Since the energy of the photon is conserved, there are more infrared photons emitted then visible light photons absorbed.
Some materials are transparent to radiation.
For example clear glass is relatively transparent to visible light. Radio photons can pass through a brick wall because their energy is so low that they are not absorbed by the electrons. All rights reserved. Privacy Policy .