## Quantum World 1.33

Dominique S 4E
Posts: 11
Joined: Fri Sep 28, 2018 12:27 am

### Quantum World 1.33

The velocity of an electron that is emitted from a metallic surface by a photon is 3.6 " 103 kms1.
(a) What is the wavelength of the ejected electron?

Andrea Zheng 1H
Posts: 61
Joined: Fri Sep 28, 2018 12:26 am

### Re: Quantum World 1.33

You would want to use the De Broglie equation for this question (wavelength = h/m*v). You would need to look up the mass of the electron and then you are given Planck's constant and the velocity. From there, you would get the wavelength of the ejected electron. Make sure to convert everything to SI units so the units can cancel to get the final answer in meters.

lindsey_ammann_4E
Posts: 61
Joined: Fri Sep 28, 2018 12:26 am

### Re: Quantum World 1.33

Does anyone know with certainty that we will be given the mass of an electron on the test?

Nick Bazett 1F
Posts: 32
Joined: Fri Sep 28, 2018 12:15 am

### Re: Quantum World 1.33

If you want to memorize the mass of an electron it is 9.10938356 × 10-31 kilograms, not sure whether Professor Lavelle has told us whether or not it will be given.

Chem_Mod
Posts: 17461
Joined: Thu Aug 04, 2011 1:53 pm
Has upvoted: 391 times

### Re: Quantum World 1.33

mass of electrons will be given on the equation sheet