rvanveshana.com
Photon E = 3.44 eV
Light Source (Ī» = 360nm)CathodeĪ¦ = 3eVAnode

Live Telemetry & Summary

Observe the electron emission. Short wavelengths (UV/Blue) have high energy per photon, triggering electron ejection. Long wavelengths (Red) do not carry enough energy per photon, resulting in zero emission regardless of light intensity.

Photon Energy (E):3.444 eV
Metal Work Function (Ī¦):3.00 eV
Cutoff Wavelength (Ī»ā‚€):413.3 nm
Max Electron Kinetic Energy (K_max):0.444 eV
Stopping Potential (Vā‚€):0.444 V

Variable Adjuster

Wavelength (Ī»)360nm
200700
Work Function (Ī¦)3eV
25.5

Photoelectric Effect

PHEL

The Photoelectric Effect is the emission of electrons when light shines on a metal surface. Quantum mechanics explains that light is composed of discrete packets of energy called photons. If a photon's energy exceeds the work function (binding energy) of the metal, an electron is ejected immediately.

Kmax=hfāˆ’Ī¦=hcĪ»āˆ’Ī¦K_{max} = hf - \Phi = \frac{hc}{\lambda} - \Phi

Whiteboard Solver Steps

Step 1

Photon Energy (E) Calculation

The energy of incident photons depends solely on the wavelength of light.

E=hcĪ»=1240 eVā‹…nm360 nm=3.444 eVE = \frac{hc}{\lambda} = \frac{1240\text{ eV}\cdot\text{nm}}{360\text{ nm}} = 3.444\text{ eV}
Step 2

Threshold Wavelength (Ī»ā‚€)

Light with a wavelength longer than this threshold does not carry enough energy per photon to eject electrons.

Ī»0=hcĪ¦=1240 eVā‹…nm3.00 eV=413.3 nm\lambda_0 = \frac{hc}{\Phi} = \frac{1240\text{ eV}\cdot\text{nm}}{3.00\text{ eV}} = 413.3\text{ nm}
Step 3

Max Kinetic Energy (K_max)

Since the photon energy exceeds the work function, electrons are ejected with surplus energy as kinetic energy.

Kmax=hfāˆ’Ī¦=Eāˆ’Ī¦=3.444āˆ’3.00=0.444 eVK_{max} = hf - \Phi = E - \Phi = 3.444 - 3.00 = 0.444\text{ eV}