E=hv is an equation important when dealing with light. E refers to the energy of a photon; h is Planck's constant and v is the wavelength. According to this equation, light particles called photons travels in packets of energy. This is important in pv cells because this is the technology used to harness solar energy which is converted to electricity. The amount of energy should be estimated to know the appropriate material of construction of the pv cell to achieve optimum conditions. In this way, the pv cell could maximize the sun's energy.
In the attachment are some examples:
The answer is iguana because they are the only animal that changes color
It is part of our nervous system and uses stimuli to respond to an event that is happening. The five senses are motor receptors making you move your muscles to respond to that event that is happending