Question

A metal of work function `4eV` is cexposed to a radiation of wavelegth `140xx10^(-9)m`. Find the stopping potential.

Answer 1

`E=(hc)/lambdaE=(6.62xx10^(-34)xx3xx10^(8))/(140xx10^(-9)xx1.6xx10^(-19))eV=8.86eV`
work function `W_(0)=4eV`
`eV_(0)=E-W_(0)=8.86-4=4.76eV`
`:.` Stopping potential `V_(0)=4.86V`