In: Physics
Part B
In another experiment, the intensity of the incident light and the
temperature of the metal are held constant. Assuming that the
initial light incident on the metal surface causes electrons to be
ejected from the metal, what happens if the frequency of the
incident light is increased?
Check all that apply.
The work function of the metal increases.
The number of electrons emitted from the metal per
second increases.
The maximum speed of the emitted electrons
increases.
The stopping potential increases.
In photo electric effect, Electron \(\mathrm{KE}=\) photon energy - work function. \(\frac{1}{2} m v^{2}=h f-\phi\)
and
Stopping potential \(=\frac{\mathrm{KE}}{\text { electronic charge }}\)
Therefore, increasing frequency \(f\) then, increasing photon energy \(\Rightarrow\) increasing \(\mathrm{KE}\) enegy \(\Rightarrow\) increasing electron speed \(\mathrm{v}\) and stopping potential.
Hence the answers are
The maximum speed of the emitted electrons increases.
The stopping potential increases.