Chapter 39, Problem 56E

(a)

To determine

Recoil speed of the atom that emits a photon of wavelength $\lambda$.

(b)

To determine

Kinetic energy $K$ of the recoiling atom.

(c)

To determine

The ration of $\frac{K}{E}$, where $E$ is the energy of the emitted photon and to check whether the recoil of the atom is more important for small or large atomic masses also to check it is important for long or short atomic masses.

(d)

To determine

The value of $K$ and $\frac{K}{E}$ for a hydrogen atom that emits an ultraviolet photon of energy $10.2\text{eV}$ and check whether the recoil is an important consideration in this process.