Frequency of light to eject electrons from gold

[mhooker_10]

What frequency of light must be used to eject electrons from a gold surface with a maximum kinetic energy of 6.48×10(−19)J ?

The work function of gold is 4.58 eV.

f=

 

[mgb_phys]

You have to at least attempt an answer to a homework question.
Whats the energy of a photon, in terms of frequency?

 

[mhooker_10]

I used the formula for K(max) and solved for f and got 6.91 x 10(33)...and that not the right answer

 

[mgb_phys]

So you need to supply enough energy to overcomethe work function and then supply the KE.
So convert the work function into joules and add to the ke.
Then you just need the energy of aphoton in terms of frequency.

oops - you didn't post in the HW forum, so didn't get the list of things to do.

 

[mhooker_10]

Nevermind...I figured it out