00:01
For this question we're asked to find the energy for an x -ray that has a wavelength of 10 picometers.
00:09
So the equation that we're gonna use is that the energy is equal to h, which is planck's constant, times c, the speed of light, divided by the wavelength.
00:22
So we already know planck's constant, which is 6 .63 times 10 to the negative 34th joules times second, times the speed of light, which is three times 10 to the eighth meters per second, divided by the wavelength.
00:45
Now, before we put the wavelength in there, notice that the speed of light is in meters, but the wavelength is in picometers.
00:51
So before we input the value for wavelength, we need to change picometers into meters, which they give us that conversion in the problem.
01:03
So we're gonna take it times conversion where one times 10 to the negative 12th meters for every one picometer, picometer units cancel out...