00:07
Let's consider the energy levels of a hypothetical atom for a.
00:11
What is the wavelength of a photon needed to excite an electron from e1 to e4? so we'll first calculate delta e, which is going to be equal to e4 minus e1.
00:23
It's be minus 1 .0 times 10 to the negative 19 joules, minus 15 times 10 to the negative 19 joules.
00:34
And delta e works out to 1 .4 to the negative 19 joules.
00:37
Times 10 to the negative 18 joules.
00:40
And using this, let's calculate the wavelength.
00:44
Delta e is equal to hnew, which is equal to h .c.
00:56
Lambda.
00:57
So delta e is equal to 1 .4 times 10 to the negative 18 joules, 6 .63 times 10 to the negative 34 joules per second.
01:15
And this is 3 .00 times 10 to the 8 meters per second over the wavelength.
01:23
Solving for lambda, the wavelength, we find that is equal to 1 .4 times 10 to the negative 7 meters...