1. The problem statement, all variables and given/known data Consider a particle of mass m in the potential V(z)=mgz z>0, infinity if z<0 Show that the wavelength of a neutron (m~1000MeV/c^2) is on the order of 10um. 2. Relevant equations p=(2m(E-mgz))1/2 [itex]\lambda[/itex]=h/p 3. The attempt at a solution The most direct solution would seem to simply be h/(2m(E-mgz))1/2 (with appropriate substitutions) however, that still leaves the factors of g and z to be resolved... I could take z as 1, but there's still g with a units problem (m/s/s vs MeV and MeV/c^2). Any suggestions?