Answer
See explanation.
Work Step by Step
a. $E=\frac{hc}{\lambda}=\frac{(4.136\times10^{-15}eV)(3.00\times10^8 m/s)}{0.20\times10^{-9}m}=6.2keV$
b. $E=\frac{p^2}{2m}=(\frac{h}{\lambda})^2 \frac{1}{2m}=\frac{h^2}{2m \lambda^2}$
Evaluate using the electron’s mass to find 38 eV.
c. Evaluate the expression using the alpha particle’s mass to find an energy of $5.2\times10^{-3}eV$.
For a given wavelength, a photon has much more energy than an electron.
The electron has more energy than an alpha particle.
