The wavelength associated with an electron moving with a velocity of 1010  cm per  sec.

Mass of the electron = 9.10  ×  10-28  gVelocity of electron = 1010  cm  per sec.h=6.62  ×  10−27  erg−secλ  =  hmv =6.62 ×  10−27  9.10 ×  10−28   ×  1010  =7.72  ×  10−10  cm=0.0772Ao