127k views
4 votes
The de broglie wavelength of an electron is 8.7 Ã 10-11 m. the mass of an electron is 9.1 Ã 10-31 kg. the velocity of this electron is ________ m/s.

User Schatten
by
7.1k points

1 Answer

2 votes
wavelength of an electron l = h/p = 8.7 x 10^-11 h --> Planck's Constant m --> Momentum Wavelength l = h/p = h/mv = > v = h/(m*l) From the given values, m = 9.1 x 10^-31 kg l = 8.7 x 10^-11 m h = 6.626x10^-34 Js v = 6.626x10^-34/ ((9.1 x 10^-31)*(8.7 x 10^-11)) The velocity of electron v = 8.37x10^6 m/s
User Gavin Stanley
by
8.3k points