## De Brogile's Equation [ENDORSED]

$c=\lambda v$

Katherine Osby
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### De Brogile's Equation

Question: For De Brogile's equation, should you always make sure that mass is in terms of kilograms?

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### Re: De Brogile's Equation

Yes, it must be converted to kilograms for the equation to work

Chem_Mod
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### Re: De Brogile's Equation  [ENDORSED]

The de Broglie equation, $\lambda = \frac{h}{p}$, can be used with any unit of mass provided that you convert h, Planck's constant, to that mass. By convention, Planck's constant is in Joules, $6.626 \times 10^{-34} J \cdot s$, where Joules is in $J = kg \cdot m^{2} \cdot s^{-2}$. One can see that Planck's constant is using kilograms so, unless you want to convert Planck's constant, the equation as given works for kilograms only.

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### Re: De Brogile's Equation

Yes. You always need to keep the units in mind. If not, the equations do not apply.