The Photoelectric Effect

Given the following data for incident wavelength and the stopping potential obtained from an experiment on photoelectric effect, estimate the value of Planck's constant and the work function of the cathode material. What is the threshold frequency and corresponding wavelength? What is the most likely metal used for emitter?

Radiation of wavelength $4500 \stackrel{\mathrm{o}}{\mathrm{A}}$ is incident on a metal having work function $2.0 \mathrm{eV}$. Due to the presence of a magnetic field B, the most energetic photoelectrons emitted in a direction perpendicular to the field move along a circular path of radius $20 \mathrm{cm}$. What is the value of the magnetic field B? Take the mass of electron$=9.1\times {10}^{-31} \mathrm{kg}$, the charge of electron $=1.6\times {10}^{-19} \mathrm{C}$, Planck's constant $=6.6\times {10}^{-34} \mathrm{J} \mathrm{s}$.

Photocurrent recorded in the micro ammeter in an experimental set-up of photoelectric effect vanishes when the retarding potential is more than $0.8 \mathrm{V}$ if the wavelength of incident radiation is $4950 \stackrel{\mathrm{o}}{\mathrm{A}}$. If the sources of incident radiation is changed, the stopping potential turns out to be $1.2 \mathrm{V}$. Find the work function of the cathode material and the wavelength of the second source. Take $h=6.6\times {10}^{-34} \mathrm{J} \mathrm{s}$ and $c=3\times {10}^8 \mathrm{m}/\mathrm{s}$.

Observations from an experiment on photoelectric effect for the stopping potential by varying the incident frequency were plotted. The slope of the linear curve was found to be approximately $4.1\times {10}^{-15} \mathrm{V} \mathrm{s}$. Given that the charge of an electron is $1.6\times {10}^{-19} \mathrm{C}$, find the value of the Planck's constant $\mathrm{h}$.

What will be the energy of each photon in monochromatic light of frequency $5\times {10}^{14} \mathrm{Hz}$?

It is observed in an experiment on the photoelectric effect that an increase in the intensity of the incident radiation does not change the maximum kinetic energy of the electrons. Where does the extra energy of the incident radiation go? Is it lost? State your answer with explanatory reasoning.

Explain the inverse linear dependence of stopping potential on the incident wavelength in a photoelectric effect experiment.

Polychromatic (containing many different frequencies) radiation is used in an experiment on photoelectric effect. The stopping potential.

A photocell is used to automatically switch on the street lights in the evening when the sunlight is low in intensity. Thus it has to work with visible light. The material of the cathode of the photo cell is

A particular metal used as a cathode in an experiment on photoelectric effect does not show photoelectric effect when it is illuminated with green light. Which of the colours in the visible spectrum are likely to generate photocurrent?