The answer is in the meaning of the word itself. Kinetic (adjective) * relating to or resulting from motion * depending on movement for its effect Hence, kinetic energy will be applicable only for moving bodies. read more
The velocity which we obtain with respect to the reference velocity is called relative velocity. And kinetic energy is the energy of a body by virtue of its motion, which means it depends on velocity (relative velocity). So when relative velocity is zero, kinetic energy is also zero. read more
A gas, or any matter, would have zero kinetic energy when its temperature reaches absolute zero, zero degrees Kelvin. read more