Question

Question #3eff3

Answer 1

`E = hnu` and `c = nu*lambda`

`E_1 = (6.626*10^-34J*s)*(2.98*10^8m/s)/((6.42*10^-5cm) * (10^-2m)/(cm)`

These units may seem confusing, but this problem is making me keep track of them, you must convert the wavelength or else your answer is wrong.

`therefore E_1 approx 3.08*10^-19 J`

`E_2 = (6.26*10^-34J*s)*(5.82*10^14s^-1)`

`therefore E_2 approx 3.86*10^-19J`

As you can quantitatively see, red light is lower energy than green light. We empirically know this due to the electromagnetic spectrum, and the Doppler effect, among other things.