hi

 

for ur question about threshold frequency, yes if the frequency is greater than the threshold frequency only e will b emitted bcoz

 

h - h = 1/2mv²=K.E              (=threshold frequency)

if the given frequency is equal to the threshold frequency then the L.H.S of the eqn will become 0 i.e K.E will b 0. thus if the energy of the e is 0 it will not b emitted.thus  >  is the condition for the emission of e.  (e=electron)

 

hope this helps u

if yes then plz rate me.

 

!!!!!!!!!