A metal has a work function `phi_(0)` and its corresponding threshold wavelength is `lambda_(0)`. If the threshold wavelength for a metal whose work function is `(phi_(0))/(3)` is `n lambda_(0)`, then what is the value of n ?

Answer

3

Explanation

We know, `phi _(0) = ( hc)/( lamda _(n))`
` therefore ( phi _(0))/( phi ._(0)) = ( lamda ._(0))/( lamda _(0))`
Here, `phi ._(0) = ( phi _(0))/(3) `
` therefore (lamda ._(0))/( lamda _(0)) = 3`
`therefore lamda ._(0) = 3 lamda _(0)`
` therefore n = 3`