Question

10. The uncertainty in determining the duration during which an electron remains in a particular energy level before returning to the ground state is 2x10⁻⁹s. Calculate the uncertainty in determining its energy at that level.

Accepted Answer

The uncertainty principle is expressed by: Δx.Δp ≥ h or ΔE.Δt ≥ h, where h = h/2π = 1.054x10⁻³⁴ Js. Given Δt = 2x10⁻⁹s: ΔE ≥ h/Δt = 1.054x10⁻³⁴/(2x10⁻⁹) = 5.27x10⁻²⁶ J.

WAEC Physics 2011 Theory — Question 14

Sign up free to unlock