According to de Broglie, the matter should exhibit dual behaviour, that is both particle and wave-like properties. However, a cricket ball of mass 100 g does not move like a wave when it is thrown by a bowler at a speed of 100 km/h. Calculate the wavelength of the ball and explain why it does not show wave nature.
According to de-Broglie,
λ = h / mv ,
where λ is the wavelength of the particle-wave, m and v are the mass and velocity of the particle respectively and h = Planck’s constant = 6.626 X 10-34 J.s
hence, in this case, λ = 
now, m = 100g = 0.1 kg and
v=100km/h = 100 X1000/ 60X60 = 1000/36 m/s
λ = 
= 238.5 X 10-36 m-1
The range of wavelength is very small here (10 -36), therefore the wave nature of the ball cannot be detected.
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