## How to find work function

Savannah Mance 4G
Posts: 107
Joined: Fri Aug 30, 2019 12:17 am

### How to find work function

On the homework for problem 1B.15, the equation gives the velocity of the photon. I used the velocity to find the kinetic energy of the photon. However, the problem asks me to find the wavelength. But, there is no given work function or energy of the photon. How am I suppose to solve for the wavelength?

SGonzales_3L
Posts: 55
Joined: Thu Jul 11, 2019 12:17 am

### Re: How to find work function

Given the velocity of the photon, we can use De Broglie's Equation: . We know the values for Planck's constant (6.626 x 10-34 Js) and for the mass of an electron (9.109 x 10-31 kg). Since we are given the velocity, we can just solve for wavelength.

Rebecca Epner 4A
Posts: 53
Joined: Sat Aug 17, 2019 12:18 am

### Re: How to find work function

In order to use the de Broglie relationship, you first need to put m in terms of m.s^-1. Then you can solve for the wavelength by using Plancks constant and the known mass of e-