Define photoelectric work function. How is it related to thresold frequency?

Explanation

Work Function W0 of a surface is the minimum amount of energy required to eject an electron from a surface with zero kinetic energy.
Relation between `W_(0)` and `v_(0)`
From Einstein.s photoelectric equation, we have
`hv = W_(0) +1/2 mv^(2)`............. (i)
When `v = v_(0)v=0`
So, eq (i) becomes
`hv_(0) =W_(0) +0`
or `W_(0) =hv_(0)`