Light and X Rays

1. Feb 19, 2008

zachcumer

Hey here is the question I have to answer...

What is the principal difference between light and an X-ray?

I thought that X rays have short wavelengths, and light has long?

Thanks

Last edited: Feb 19, 2008
2. Feb 19, 2008

zachcumer

hello?

3. Feb 19, 2008

zachcumer

anyone? hello? anyone there?

4. Feb 19, 2008

cepheid

Staff Emeritus
Yes, visible light and X-rays are BOTH electromagnetic radiation. The only thing that distinguishes them is their wavelength. It's true that the wavelength of X-rays is shorter than that of visible light, but the words "short' and "long" in your answer are pretty meaningless unless you actually quantify the wavelength.

5. Feb 19, 2008

zachcumer

so what I was going to put down was the principal differences are that visible light has longer wavelengths compared to x rays which have shorter wavelengths.

6. Feb 19, 2008

cepheid

Staff Emeritus
That's fine, I was just pointing out that if you write it that way, the question naturally arises: shorter than WHAT? Longer than WHAT?

"Shorter" and "longer" imply a comparison

If you write: "The principal difference is the wavelength of the two types of EM radiation. The wavelength of visible light is longer than the wavelength of an X-ray."

EDIT: Or you could just omit the 4 words "which have shorter wavelengths" from the end of your answer.

Either way, that's a better wording because it makes it clear WHAT the comparison is. However, the answer is still vague. If you actually specified how many orders of magnitude longer the wavelength of visible light was, that would be even better:

The wavelength of visible light is 10^{blah} times longer than the wavelength of x-rays.

Even better would be to explicitly state the wavelengths. Physics is a quantitative science.