The uncertinty in determining the duration during which an electron remains in a particular energy level before returning to the ground state is 2.0 x 10\(^...

Assessment: WAEC SSCE - Physics - 2006 (Essay) Subject: Physics

Question 1 Report

The uncertinty in determining the duration during which an electron remains in a particular energy level before returning to the ground state is 2.0 x 10\(^{-9}\)s. Calculate the uncertainty in determining its energy at that level [Take \(\frac{h}{2\pi} = h = 1.054 \times 10^{-34}\) Js]

 

Answer Details

The Heisenberg uncertainty principle relating energy and time is:

\[ \Delta E \cdot \Delta t \geq \frac{h}{2\pi} \]

Taking the equality and making \(\Delta E\) the subject:

\[ \Delta E = \frac{h/2\pi}{\Delta t} = \frac{1.054 \times 10^{-34}}{2.0 \times 10^{-9}} \] \[ \Delta E = 5.27 \times 10^{-26}\ \text{J} \]

The uncertainty in the energy of the level is \(5.27 \times 10^{-26}\ \text{J}\).

In electron-volts, \(\Delta E = \dfrac{5.27 \times 10^{-26}}{1.6 \times 10^{-19}} = 3.29 \times 10^{-7}\ \text{eV}\).

Download The App On Google Playstore

Everything you need to excel in your exams

Green Bridge CBT Mobile App
Personalized AI Learning Chat Assistant
200,000+ Exam Questions Across IGCSE, JAMB, WAEC & NECO
Over 3,900 Lesson Notes
Offline Support - Learn Anytime, Anywhere
Green Bridge Timetable
Literature Summaries & Potential Questions
Track Your Performance & Progress
In-depth Explanations for Comprehensive Learning