Question

The work function for metals x, y and are respectively
1.92ev, 20 ev and 50 ev. According to einstein asian,
the metal which will emit photoelectrons for a radiation of
wavelength 4100A" is are:
a) x only b) X and Y only c) X, Y and a d) x and z​

Answer 1

Answer:

option a is correct

firstly calculate energy of metal which emit photoeltron in electovolt unit ,, energy = hc/ lemda where h is plank cont . ( 6.67×10^-34) and c is speed of light ( 3×10^8) and lemda (4100×10^-10m) and this energy in joule to convert into ev so divide this energy into 1.6×10^-19 but this long process for very quick ans use this formula energy (in ev) = 12400/ lemda then you got 3.02 ev and work function is less than this value for emiting photoeltron so only x