Electron and matter waves: WE NEED HELP

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Electron and matter waves: WE NEED HELP!

Homework Statement


Calculate the de Broglie wavelength of (a) a 1.00Kev electron, (b) a 1.00Kev photon, and (c) a 1.00KeV neutron


Homework Equations


K = mv^2 / 2

p = mv

p = sqrt 2KM

m of electron is 9.11 * 10^-31 kg

1 ev = 1.6 * 10^-19 Joules

change in Lamda = h / p

h = 6.63 *^-34


The Attempt at a Solution




Is this correct. Here's what we tried.
)
change in lamda = 6.63 * 10 ^ -34 / sqrt(2) ( 9.11 * 10 ^-31) ( 1KeV) (1000eV / 1Kev) (1.6 * 10 ^ -19 J)

=



=
 
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Looks like you are setting things up okay. So what is the result of your calculation?

A couple of minor points:
The energy and mass belong inside the sqrt(), it's not clear if you are meaning to do that from what you wrote.
The "J" at the end of your expression should really be "J/eV" to do the units conversion properly.
 

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