Final answer:
The time it takes a fully energized x-ray tube to return to a non-energized state is termed the extinction time. It's a period for the dissipation of residual energy from the x-ray tube. This concept is crucial for the safety and technical management of x-ray equipment.
Step-by-step explanation:
The time it takes a fully energized x-ray tube to return to a non-energized state is termed the extinction time. The term extinction time refers to the duration required for an x-ray tube that has been turned off to dissipate its residual energy and stop producing x-rays. This is an important safety and technical consideration when operating x-ray equipment, as one must wait for the extinction time to pass before assuming the absence of radiation.
In the context of radiation exposure, when calculating the temperature increase of a researcher exposed to x-rays, we need to consider the energy absorbed by the tissue and the specific heat capacity of the tissue. X-ray photons have significant energy, in this instance 200 keV, and when a large number of these photons are absorbed by the tissue, it can lead to a temperature increase due to the energy transfer.
The fact that medical diagnostic x-ray machines cannot produce the intensity mentioned in the question highlights the safety measures in place to prevent such dangerous levels of exposure during medical procedures.