18.5k views
5 votes
what is the maximum kinetic energy in ev of electrons ejected from a certain metal by 406 nm em radiation, given the work function is 2.31 ev?

User Nahtnam
by
7.4k points

1 Answer

4 votes

Final answer:

The maximum kinetic energy of electrons ejected from a metal by 406 nm EM radiation, with a work function of 2.31 eV, is 0.745 eV.

Step-by-step explanation:

To calculate the maximum kinetic energy (K_max) in electronvolts (eV) of electrons ejected by electromagnetic (EM) radiation from a metal, one can use the photoelectric effect equation:

K_max = E_photon - Φ

Where E_photon is the energy of the incident photon and Φ is the work function of the metal.

The energy of a photon (E_photon) can be calculated using the equation:

E_photon = (hc) / λ

Where h is Planck's constant (4.135667696 × 10^(-15) eV·s), c is the speed of light (approximately 3 × 10^8 m/s), and λ is the wavelength of the incident light in meters.

For the radiation with a wavelength of 406 nm (which is 406 × 10^(-9) meters) and a work function of 2.31 eV for the metal, the maximum kinetic energy of the ejected electrons would be calculated as:

E_photon = (4.135667696 × 10^(-15) eV·s × 3 × 10^8 m/s) / (406 × 10^(-9) m) = 3.055 eV

Thus, the maximum kinetic energy (K_max) would be:

K_max = 3.055 eV - 2.31 eV = 0.745 eV

So the maximum kinetic energy of electrons ejected from the metal by 406 nm EM radiation, given the work function of 2.31 eV, is 0.745 eV.

User WigglyWorld
by
7.6k points