## Photoelectric Effect Module Question 28

Juliet Stephenson 4E
Posts: 100
Joined: Wed Sep 18, 2019 12:21 am

### Photoelectric Effect Module Question 28

Hi, I was hoping someone could walk me through Problem 28 on the Photoelectric Module.

28. Light hits a sodium metal surface and the velocity of the ejected electron is 6.61 x 105 m.s-1. The work function for sodium is 150.6 kJ.mol-1.
A. What is the kinetic energy of the ejected electron?
C. What is the frequency of the incident light on the sodium metal surface?

Thank you!

Ashley R 1A
Posts: 41
Joined: Sat Aug 24, 2019 12:16 am

### Re: Photoelectric Effect Module Question 28

I posted about this question the other day haha :) For part a), you use the e=1/2 m v^2 equation since e = kinetic energy of the electron. You're given velocity, and then the mass of an electron is constant at 9.109 x 10^-31 kg. Then, now that you have e, you can use the equation e = hv to calculate the frequency, since your only unknown is v

Juliet Stephenson 4E
Posts: 100
Joined: Wed Sep 18, 2019 12:21 am

### Re: Photoelectric Effect Module Question 28

Thank you Ashley!