Question

What is the de Broglie wavelength of a ball of mass 0.12 Kg moving with a speed of 20 ` " ms"^(-1)` ? What can we infer from this result ?

Answer 1

Given , m = 0.12 kg, v = 20 m/s , h = `6.63 xx 10^(-34)` j-s,
`lambda = h/(mv) = (6.63xx10^(34))/(0.12xx20) = (6.63 xx 10^(-34))/2.4 :. lambda = 2.762 xx 10^(-34) xx 10^(-34) " m " = 2762 xx 10^(-21) `
The wave length of ball is very very small . Hence , its motion can be observed .