Does the earth become lighter when you burn wood ie does energy have mass?

Answer 1

Einstein's equation, E=MC^2, describes the relationship between energy and mass. Pure energy (photons) travel at the speed of light, and have no mass.

However, when a photon strikes a nucleus, it's energy is imparted into the nucleus. In some cases, this results in an increase, albeit small, in mass.

The process of Fission actually converts mass into energy.

When you burn wood, much of it is converted into particles, which still have their mass. Some is converted into light and other forms of EM radiation, which does not have mass. Technically, then, the system loses mass, and would become lighter.

Realize, however, that when this light is absorbed in the surrounding environment, most is converted back into matter.

This is a rather odd application of some more advanced physics, and I'm sure there's some other technicalities that can shed more light on the subject. In a simplistic statement, though, YES...burning wood would make the Earth lighter.

Answer 2

The energy you are getting from burning wood is stored as potential energy within the molecular bonds.

Answer 3

No the earth has the same mass all the time, Things ony change from one form to another..... No weight is lost or gained unless it comes from space...