Neutron diffraction is used in determining the structures of molecules.

(a) Calculate the de Broglie wavelength of a neutron moving at 9.00% of the speed of light.
__ m
(b) Calculate the velocity of a neutron with a wavelength of 65 pm (1 pm = 10-12 m).
__m/s

2 answers

wavelength = h/mv will work both of these. m is in kg and v in m/s.
A) 6.63*10-34/1.675*10-27*0.01*3.00*10^8
=1.32*10^-13m