Question

Is there an Advantage in limiting your exposure to radiation source to the shortest time possible? Explain

Answer 1

To a significant extent, yes. Radiation is not like poison, in that you can "consume" some and it can do damage to you later, at leisure. For the most part, radiation does its damage immediately (although the effects may only be felt over time), and it begins when you begin exposure, and then goes on until you stop. The longer you're exposed, the more damage. It's just like the fact that you get wetter the longer you stand in the rain.

Generally speaking, the harm radiation does you, if it is harmful at all, is proportional to the total energy you absorb, and that is equal to the intensity of the radiation multiplied by the length of time to which you are exposed to it.

There are caveats: it is possible that below a certain lower threshold, radiation does no harm no matter how long you are exposed, and may even do some good. The hypothesis is called "radiation hormesis" and is a matter of vigorous debate:

http://en.wikipedia.org/wiki/Radiation_hormesis