what is the meaning of this? please explain.?

Question

Exposure to ultraviolet rays, x-rays, or gamma rays cannot be made perfectly safe. On the other hand, exposure to all lower-frequency Electromagnetic radiation can be made perfectly safe by limiting intensity. Please Explain.

Answer 1

Or can it?
What about long term exposure to a low frequency EMF, like people living under power lines?
I think the jury is still undecided.

Exposure to high AND low frequency EMF radiation can be lowered to an "acceptable risk" but not eliminated.

For example, gamma exposure radiation can be lowered so that it is the same as naturally occurring background, which can NOT be eliminated, and thus be made acceptable.

There is also a risk assessment formula that industry, scientists and government have agreed to for acceptable radiation levels based on extrapolating backwards known (harmful) data.

Answer 2

The Energy of a wave (or ray) is governed by its frequency from the equation-:

Energy = Plancks Constant x Frequency

Plancks Constant is well, er a tiny constant (6.63 x 10^-34 Joule seconds)

Therefore the energy of a particular wave purely relies on frequency. Long wavelengths have lower frequencies from the equation-:
Speed of Light = Wavelength x Frequency

Therefore the energy of waves (or rays) from longer wavelengths is not high, whereas the energy of X-Rays and Gammas can be extremely high - this means they can penetrate further into a substance and also damage cells etc. (sometimes damaging DNA and causing cells to replicate incorrectly - thus can cause cancer and other nasties).

All waves (or rays) in the EM spectrum are actually classed as Photons, whether it be a Radio Photon (Radio Wave) or an X-Ray Photon. Have a look at some experiments regarding this-:

The Compton Effect
The Photo-Electric Effect

These also show that photons can actually behave as particles aswell (known as wave-particle duality) - its all quite interesting really !! ;o)

Answer 3

ok here is it
more frequency is having more energy because speed is almost always nearly same
so if there is more energy then it surly would do more work and so will not be safe as
waht would the photons do to your skin?
they will roast is if they have the power i.e energy to do so

but if intensity is made lower of lower i.e infra red waves, which means there will be less photons are running through in the same time, and as is posses lower energy so it would not harm the skin or inner side as much as the ultra violet
but if the intensity is made very low then it will become harm less