Can Planck's Constant Equation Be Used to Calculate Particle Speed?

[fk378]

This is a general question..

For the equation c=hv
where c=speed of light, h=Planck's constant, and v=frequency...

Can u (speed of a particle/electron) be substituted in for c? ie, if given the frequency of an electron and we need to find its speed, can we use this equation (u=hv) or must we get to the answer by using other equations?

 

[Vagrant]

This is a general question..

For the equation c=hv
where c=speed of light, h=Planck's constant, and v=frequency...

Isn't this equation E=hv?

 

[fk378]

Oh sorry, I meant to refer to the equation c=lambda(v)

 

[chemisttree]

Soooo, what is the question?

 

[fk378]

For c=(lambda)(frequency)
where c=the speed of light, can you replace c with u (speed of a particle)? Say, you're given the frequency and the wavelength of a particle and you need to find its speed, can you use this equation, or must you find it from another equation(s)?

 

[Hootenanny]

For c=(lambda)(frequency)
where c=the speed of light, can you replace c with u (speed of a particle)? Say, you're given the frequency and the wavelength of a particle and you need to find its speed, can you use this equation, or must you find it from another equation(s)?

No, the equation you have quoted there is called the 'Dispersion relation for EM-waves in a vacuum' and is therefore only valid for EM-waves in a vacuum. You would have to use other equations, namely the de Broglie relations.