A sample of silver (with work function φ = 4.52 ev) is exposed to an ultraviolet light source (λ= 200 nm), which results in the ejection of photoelectrons. what changes will be observed if:
Work function of metal = hc/e
h=planck's constant
c=speed of light in vacuum
= threshold wavelength = 285nm
e=1.6 x 10^-19
So = (6.63x10^-34)x (3 x 10^8)/(285x10^-9 x 1.6 x 10^-19) =4.36 eV
Maximum energy of emitted electrons
= Energy incident - work function
= hc/e (where =140nm)
=(6.63x10^-34)x (3 x 10^8)/(140x10^-9 x 1.6 x 10^-19) - 4.36
=8.88 - 4.36 = 4.52 eV
