## HW Question 1.23 (6th edition)

$c=\lambda v$

Shreya Tamatam 3B
Posts: 30
Joined: Fri Sep 28, 2018 12:25 am

### HW Question 1.23 (6th edition)

The question says "The y-ray photons emitted by the nuclear decay of a technetium-99 atom used in radiopharmeceuticals have an energy of 140.511 keV. Calculate the wavelength of these y-rays."

To solve this, do we first convert keV to joules, and then combine the equations E=hv and (lambda)v=c and solve for lambda? Can anybody explain how they approached the problem?

Neil Hsu 2A
Posts: 61
Joined: Fri Sep 28, 2018 12:16 am

### Re: HW Question 1.23 (6th edition)

That's exactly how I would approach this problem. Convert keV to joules and then solve for frequency using E = hv and then for wavelength using c = (lambda)v. Alternatively, there's another value for Planck's Constant in eV where h = 4.1357 × 10^-15 eV s. However, it's all the same.