Question

Electrons of wavelength 1.5 nm are emitted from a material when light of wavelength 350nm is incident on it. What is the work function of this material?

Answer 1

3.5434 eV

Step-by-step explanation:

For a particle with kinetic energy E and mass m , the wavelength associated is given by the following relation,

`\lambda=(h)/(√(2mE) )`

E =
`(h^2)/(2m\lambda^2)`

Putting the values we get

E =
`\frac{(6.6*(10^(-34))^2}{2*9.1*10^{-31*(1.5*10^(-9))^2}}`

=1.063 x 10⁻²¹ J

= .0066 eV.

Energy of¹light in terms of eV

= 1244 / 350 = 3.55 eV.

Work function = 3.55 - 0.0066 = 3.5434 eV.