Question #e0081

1 Answer
Nov 2, 2016

By Einstein's equation for photoelectric effect we know

#hnu=hnu_o +1/2mv^2#

Where

#h->"Planck's constant"=6.626xx10^-34Js#

#nu->"frequency of incident radiation"=2.00xx10^15s^-1#

#nu_o->"thresold frequency of incident radiation"=1.67xx10^15s^-1#

#m->"mass of electron"=?#

#v->"velocity of ejected electron"=6.84xx10^5m/s#

Now

#hnu=hnu_o +1/2mv^2#

#=>1/2mv^2=h(nu-nu_@)#

#=>m=(2h(nu-nu_@))/v^2#

#=>m=(2*6.626*10^"-34"(2-1.67)*10^15)/(6.84^2*10^10)#

#=>m=(2*6.626*0.33*10^-31)/6.84^2#

#=>m=9.34xx10^-31 kg#