Waves and Electromagnetic Energy?

Question

The human eye is sensitive to what fraction of the electromagnetic spectrum, assuming a spectral a special range of 10^4 to 10^20 Hz? If we came from the planet Krypton and had X-ray vision (that is, if our eyes were sensitive to X rays in addition to visible light), how would this fraction be change?

Answer 1

You couldn't look the numbers up?

The visible spectrum is about 400–800 THz, or 400-800 E12 or about 400 E12 wide.

So the fraction is about 400 E12/E20 or about 4E-6, very small

xrays cover the range from 30E15 to 30E18 Hz so the new range is 30E18-400E12

which is still about 30E18 so the fraction then is 30E18 / 1E20 or about .3 of the total range.

Answer 2

I don't even bother deeply thinking about it.

Even if Superman's eyes could be sensitive to x-ray, how can he possibly see things on the other side of the wall which are not x-ray emitters?

Unless Superman is in a planet where everything emits x- rays, his spectral band of vision does not change.

Unfortunately, perception of electromagnetic energy is a two way affair. That of the emitter and the receiver. This is actually what Quantum Mechanics is. The result of observations is also influenced by the observer.