b If the electron has a speed equal to 890 106 ms what is it

(b) If the electron has a speed equal to 8.90 106 m/s, what is its wavelength?

Solution

Mass of the electron = 9.31×10^-31 Kg

Speed of the electron = 8.90106 m/s

Momentum of the electron p = mv = 9.31×10^-31×8.90106 = 8.2×10^-30 Kg.m/s

From the de Broglie hypothesis , wavelength = h/p

Where h = Planck constant = 6.626×10^-34 J.s

So, = (6.626×10^-34)/(8.2×10^-30) = 8.08×10^-5 m