Hey, this is my first week in Quantum class, going pretty well so far.(adsbygoogle = window.adsbygoogle || []).push({});

My first questoin is:

1.) What is an eV a Unit of...give it in terms of MKS

Well my answer is that it is a unit of energy, and for MKS...

1 Electron*Volt = Joules

1 electron has a charge of 1.602*10^-19 C

1 Volt = 1 J/C

Therefore

1.602*10^-19*1 means that

1 eV = 1.602*10^-19 J

Is this correct reasoning?

My next Question

Neutrons at room Temperature have a kinetic energy of around .02 eV. What is their wavelength?

KE = 0.2 eV

0.2 eV = q*V

p = h/lambda

1 eV = 1.609*10^-19 J

h = 6.626*10^-34 J*s * 1 ev/(1.609*10^-19 J)

Therefore I get Planck's constant in terms of eV

h = 4.136*10^-15 eV*s

But how do I use the 0.2 eV in terms of the p = h/lambda?

Thanks for any assistance!

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# Homework Help: A couple Quantum Questions

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