Using the spectrum

[andymacdcfc]

I have a physics exam tomorrow and I would like this to be cleared up.

Question:

UVA (315-400nm) can cause premature wrinkling of the skin whil UVB(280-315nm) gives a long lasting tan but can cause sunburn. A sun cream absorbs radiationin the range 9.2 X 10to the 14Hz to 8.6 X10 to the 14Hz.

What range of wavelength is this?

Would you do Lamda=3X10 to the 8(speed of time) divided by 9.2 X 10 to the 14?

[gen2]

Wow!  I didn't know time went that fast!

Yes, the wavelength (in metres) = the speed of light (in metres per second) divided by the frequency (cycles per second or Hz)

[andymacdcfc]

Speed of light, sorry, Anyway thanks for the answer. Im feeling confident about the exam now!

[fo3nix]

asking for the range dont forget, so you also need to work out wavelength for the upper frequency too.