A silver of radius `1 cm` and work function `4.7 eV` is suspended from an insulating thread in freepace. It is under continuous illumination of `200 nm` wavelength light. As photoelectron are emitted the sphere gas charged and acquired a potential . The maximum number of photoelectron emitted from the sphere is `A xx 10^(e) (where 1lt A lt 10)` The value of `z` is

Explanation

`R=1cm`
`f=4.7cm`
`(hc)/(lamda)=phi+eV`
`(1240(ev)(nm))/(200(nm))=4.7(ev)+eV`
`(1240)/(200)e=4.7e+eV`
`6.2-4.2=V`
`V=1.5Vol t`
`(1)/(4piepsi_0)(Q)/(R)=1.5`
`(9xx10^9)(Ne)/((1)/(100))=1.5`
`9xx10^11Ne=15`
`N=(1.5)/(9xx10^11xx1.6xx10^(-19))=(15)/(16)xx(1)/(9)xx10^8`
`=(5)/(3xx16)xx10^8=(50)/(48)xx10^7`
`Z=7`