## calculating wavelength [ENDORSED]

Melissa Ledesma 2B
Posts: 16
Joined: Sat Jul 09, 2016 3:00 am

### calculating wavelength

On homework problem 1.23 I am asked to calculate the wavelength of a y-ray. In the solution then energy of a technetium-99 atom is being multiplied by 1.6022x10^-19 but i don't know where that number came from can anyone explain why it is being multiplied by this number?

Kathrin Magdalani 3J
Posts: 22
Joined: Fri Jun 17, 2016 11:28 am

### Re: calculating wavelength

They are converting to Joules.
1 eV = 1.602177x10-19 Joule

Lucy Nakashima 1E
Posts: 21
Joined: Sat Jul 09, 2016 3:00 am

### Re: calculating wavelength

For these sorts of problems, will we be given the conversion in the question so we don't have to memorize all of the different values?

Christine_Mavilian_3E
Posts: 30
Joined: Fri Jul 22, 2016 3:00 am

### Re: calculating wavelength  [ENDORSED]

For problems involving constants and or conversion values that aren't "well known", the information will most likely be provided either on a formula sheet or within the question. If you have the Periodic Table of Elements that was given with the course reader, most of these values (i.e. constants and equations) are provided on the back.