The mathematical equation for studying the photoelectric effect is:

hν = W + 1/2 meμ^2 where ν is the frequency of light shining on the metal; W is the energy needed to remove an electron from the metal; and me and u are the mass and speed of the ejected electron, respectively. In an experiment, a student found that a maximum wavelength of 341 nm is needed to just dislodge electrons from a metal surface. Calculate the velocity (in m/s) of an ejected electron when the student employed light with a wavelength of 313 nm.

The velocity of an ejected electron when the student employed light with a wavelength of 313 nm is .

Explanation:

The mathematical equation for studying the photoelectric effect is:

We have :

Wavelength of light which can dislodge electrons from a metal surface =

Energy needed to remove an electron from the metal :

(Planck's equation)

Frequency of light shinning on metal surface =

Wavelength of light shinning on metal surface =

Mass of electron =

Velocity of electron = u

The velocity of an ejected electron when the student employed light with a wavelength of 313 nm is .