An electron falling from one energy level to another emits a photon of wavelength 550nm. What is the difference between the two energy levels?

The key equation is that of the energy of a photon.

E = hc/λ​ 

Using λ​ = 550nm gives E = 3.61x10^-19J (Remember that a nanometer is 1x10^-9 m).

Using the conservation of energy, the energy of this photon must be the energy lost by the electron.

Hence, the energy gap E = 3.61x10^-19J 

Answered by Jamie L. Physics tutor

2627 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

How does a potential divider work?


A small ball is projected with speed 15 m/s at an angle of 60 degrees above the horizontal. Find the distance from the point of projection of the ball at the instant when it is travelling horizontally.


A sample of pure gold has a density of 19300 kgm^-3. If the density of a gold nucleus is 1.47x10^17Kgm^-3, discuss what this implies about the structure of the gold atom. [4 marks]


If a 10N tension force is exerted on a steel beam (E = 200 GPa) with cross-sectional area 1cm^2, what is the stress acting on the beam? What is the change in length of the beam, if the beam is 10cm long?


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences