Question

The work function of a material is the minimum energy required to emit an electron from the material. The work function of Ag is 7.59*10^-19 J

a) If I'm in Australia (where a lot more UV light makes i through the depleted ozone layer...) and I'm wearing silver earrings, when the sun comes out irradiating me with light that has a wavelength of 185 nm, will electrons be emitted from my earrings?

b) If radiation hits me that has more energy that required to emit an electron, what happens to the additional energy?

Answer 1

a)
work function = 7.59*10^-19 J

Electron will be emitted if energy of light is more than work function
Let us calculate the energy of light

E= h*c / wavelength
   = (6.626*10^-34) * (3*10^8) / (185*10^-9)
   = 1.07*10^-18 J

Clearly energy is more than work function
SO electron will be emitted from earrings

b)
Extra energy is converted into kinetic energy of emitted electron
That is kinetic energy of emitted electron is difference between the energy of light and workfunction