## College Physics (4th Edition)

$\lambda = 2.4\times 10^{-12}~m$
We can find the energy of each photon: $E = m_e~c^2$ $E = (9.1\times 10^{-31}~kg)(3.0\times 10^8~m/s)^2$ $E = 8.19\times 10^{-14}~J$ We can find the wavelength of each photon: $E = \frac{hc}{\lambda}$ $\lambda = \frac{hc}{E}$ $\lambda = \frac{(6.626\times 10^{-34}~J~s)(3.0\times 10^8~m/s)}{8.19\times 10^{-14}~J}$ $\lambda = 2.4\times 10^{-12}~m$