## Maximum possible kinetic energy of the emitted electrons

MorganYun1H
Posts: 59
Joined: Thu Jul 13, 2017 3:00 am

### Maximum possible kinetic energy of the emitted electrons

If molybdenum is irradiated with 194 nm light, what is the maximum possible kinetic energy of the emitted electrons? The calculated minimum work is 7.22x10^-19J

Chem_Mod
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### Re: Maximum possible kinetic energy of the emitted electrons

If molybdenum is irradiated with 194 nm light, what is the maximum possible kinetic energy of the emitted electrons? The calculated minimum work is 7.22x10^-19J

Hi Morgan,

Remember this equation:
hv - phi = KE

h = Planck's constant
v = frequency
phi = work function
KE = kinetic energy

Therefore, the maximum possible kinetic energy is hv - phi.
Substitute what we know:
hv - phi
hc/lambda - phi
(6.626 x 10^-34 J s) * (3 x 10 ^8 m/s) / (194 x 10^-9 m) - 7.22 x 10^-19 J
= ___ J

MorganYun1H
Posts: 59
Joined: Thu Jul 13, 2017 3:00 am

### Re: Maximum possible kinetic energy of the emitted electrons

Oh ok, I understand. Thank you!