Question

A particle is confined to the x-axis between x = 0 and x = 1 nm. The potential energy U = 0 inside this region and U is infinite outside. What is the longest possible de Broglie wavelength for the particle?

A. infinite
B. 1 nm
C. 2 nm
D. zero
E. 0.5 nm

Answer 1

Answer:

Explanation:

According to heisenberg uncertainty Principle

Δx Δp ≥ h / 4π , where Δx  is uncertainty in position , Δp is uncertainty in momentum .

Given

Δx = 1 nm

Δp ≥ h /1nm x  4π

≥ 6.6 x 10⁻³⁴ / 10⁻⁹ x  4 π

≥  . 5254 x ⁻²⁵

h / λ ≥  . 5254 x ⁻²⁵

 6.6 x 10⁻³⁴ /. 5254 x ⁻²⁵ ≥ λ  

12.56 x 10⁻⁹ ≥ λ  

longest wave length = 12.56 n m