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A silver sphere of radius 1 cm and work ...

A silver sphere of radius 1 cm and work function 4.7 eV is suspended from an insulating thread in free-space. It is under continuos illumination of 200 jnm jwavelength light. As photoelectrons are emitted, the sphere gets charged and acquires a potential. The maximum number of photoelectrons emitted from the sphere is `Axx10^(z)"(where" 1ltAlt10)`. the value of Z is

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`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`
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