Achieve #7

[905574994]

Hi,

Could someone please help me with this question:

Suppose the typical work function of the metal is roughly 3.370×10−19 J. Calculate the maximum wavelength in angstroms of the radiation that will eject electrons from the metal.

Thanks!

[Anna Castaneda 2E]

Hi! I solved this by using the equation
lambda = ch/work function
since the work function is given. You should get a wavelength in meters, which you can then convert into angstroms.

[Albert Chen 1G]

For this question, you should use the equation lambda= hc / work function. H= plancks constant and C= speed of light. So, it would look like this:
(6.626 * 10^-34) * (3.00x10^8) / 3.370×10−19 J. Then multiply by 1x10^10 in order to get angstroms.

[Travis Wang 2G]

To go from energy to wavelength, we need to convert to frequency using E=hv and then to wavelength using lamda=c/frequency. After this is just a conversion to angstroms by moving decimal places until the power of 10 is -10. The reason it says maximum wavelength is because an increase in wavelength is a decrease in energy. If the wavelength of the radiation were any larger, there simply wouldn't be enough energy overcome the work threshold and eject electrons.