Question

The uncertainty in the position of a flying dust particle of mass 0.1 mg is found to be `10^(-4)`m. The uncertainty in the position of another flying dust particle of mass 0.5 mg is also found to be same
The uncertainty in the velocity of the lighter dust particle is nearly
A. `5 xx 10^(-24) ms^(-1)`
B. `2.5 xx 10^(-24) ms^(-1)`
C. `1.25 xx 10^(-24) ms^(-1)`
D. `5 xx 10^(-25) ms^(-1)`

Answer 1

Correct Answer - A
For lighter dust particle of mass, m = 0.1 mg
`Delta x = 10^(-4) m`
`Delta x.(m Delta v) = (h)/(4pi)`
`:. 10^(-4) m (0.1 xx 10^(-6) kg xx Delta v)`
`= (6.6 xx 10^(-34) kg m^(2) s^(-1))/(4 xx 3.14)`
or `Delta v = 5.25 xx 10^(-24) ms^(-1)`