I’m pretty sure the answer is energy because as you do ur work energy is the ability of a person or an object to do work or to cause a change. When you do work on an object, some of your energy is transferred to the object. You can think of work as the transfer of energy.
When a force causes a body to move, work is done on the object by the force. Work is the measure of the energy transfer when a force 'F' moves an object through a distance 'd'. So we say that energy is transferred from one energy store to another when work is done, and therefore, energy transferred = work done.
When light ray pass from air into water, its speed and wavelength change only the frequency of the light doesn't change.
Light travels slower in a medium of higher refractive index. It bends because of this change in speed. The wavelength of light also changes in order to maintain the constant frequency.
