The Student Room Group

work function and threshold frequency

i used hv= work function + KE
1.65eV= 2.6433x10^-19J
6.626x10^-34 x threshold frequency= work function + 2.64333x10^-19 J
not sure where to go here to work out either.
(edited 1 year ago)
Reply 1
Original post by shreya_2003
6.626x10^-34 x threshold frequency= work function + 2.64333x10^-19 J

This line is incorrect - it's not the threshold frequency, it's the frequency of the incident radiation (which you get from the wavelength).
If a photon with the threshold frequency were incident, the electron kinetic energy would be 0 (i.e. the minimum possible after being released)
Original post by Sinnoh
This line is incorrect - it's not the threshold frequency, it's the frequency of the incident radiation (which you get from the wavelength).
If a photon with the threshold frequency were incident, the electron kinetic energy would be 0 (i.e. the minimum possible after being released)


So to work out threshold frequency you would use the same equation but plug in the work funtion worked out by using the wavelengh given?
Reply 3
Original post by shreya_2003
So to work out threshold frequency you would use the same equation but plug in the work funtion worked out by using the wavelengh given?


Yeah you'd need to find a frequency (or wavelength) that gives the same photon energy as the work function

Quick Reply

Latest