What would make the de Broglie wavelength of some particle gbe large enough to be observed in an experiment?

Large/
small velocity, or
large/
small mass?

Question

What would make the de Broglie wavelength of some particle gbe large enough to be observed in an experiment? 

Large/
small velocity, or 
large/
small mass?

preetha · Answer

Sorry, got logged out of the internet.  So the wavelength is inversely proportional to mass.  Large objects have negligible wavelength.  THat is why you and me dont have a wavelenght.  And small objects like electrons have wavelengths.

anonymous · Answer

shouldnt it be like:
wavelength $\propto1/$momentum
momenum includes both mass and velocity

preetha · Answer

Yes. λ = hv/mv2 = h/mv lambda = wavelenght, mv2 = momentum. See: http://chemwiki.ucdavis.edu/Physical_Chemistry/Quantum_Mechanics/De_Broglie_Wavelength

anonymous · Answer

right.
so, both gotta change

anonymous · Answer

or more precisely, both mass and velo. "can" be changed