### Example from Friday's Lecture (10/12/18)

Posted:

**Sun Oct 14, 2018 5:00 pm**Hi,

On Friday we went over a problem at the end of class that asked if the wavelength of an electron traveling at 5.3 x 10^6 m/s could be calculated. When we plugged in the numbers, we were given 9.11 x 10^-31 kg. Where does this number come from?

Thank you!!

On Friday we went over a problem at the end of class that asked if the wavelength of an electron traveling at 5.3 x 10^6 m/s could be calculated. When we plugged in the numbers, we were given 9.11 x 10^-31 kg. Where does this number come from?

Thank you!!