Zinc has a work function of 4.3 eV. a. What is the longest wavelength of light that will release an electron from a zinc surface? b. A 4.7 eV photon strikes the surface and an electron is emitted. What is the maximum possible speed of the electron?

a

b

The velocity is  

Explanation:

From the question we are told that

   The work function of Zinc is  

Generally the work function can be mathematically represented as

=>  

Here  h is the Planck constant with the value  

  and c is the speed of light with value  

So

=>  

=>  

Generally the kinetic energy of the emitted electron is mathematically represented as

Here  E is the energy of the photon that strikes the surface

So

Here m is the mass of electron with value  

Generally  

=>  

=>    

=>    

answer and explanation;