Explanation:
From first source, kinetic energy () ejected is 1 eV and wavelength of light is
.
From second source, kinetic energy () ejected is 4 eV and wavelength of light is
.
Relation between work function, wavelength, and kinetic energy is as follows.
K.E =
where, h = Plank's constant = J.s
c = speed of light = m/s
Also, it is known that 1 eV = J
Therefore, substituting the values in the above formula as follows.
- From first source,
=
1 eV =
........... (1)
- From second source,
=
........... (2)
Now, divide equation (2) by 2. Therefore, it will become
......... (3)
Now, subtract equation (3) from equation (1), we get the following.
=
= 2 eV
Thus, we can conclude that work function of the metal is 2 eV.
