A light wave with wavelength 590nm shines upon a metal and causes it to emit an electron with a speed of 5x10^5 m/s. What is the work function of the metal?

The first step for this question is to find out how much energy is absorbed by the electron above its work function. This is found with the kinetic energy equation: K.E.=1/2mv^2 The mass of an electron is 9.1x10^-31. Using this in the above equation finds the kinetic energy to be:          K.E=0.59.1x10^-31(5x10^5)^2= 1.14x10^-19 J The kinetic energy is the energy above the work function. The energy provided from the photon of light is calculated with: E=(h*c)/L where E is the energy, h is the planck constant, c is the speed of light, and L is the wavelength.Inputting the correct values into the above equation gives: E=6.63 x 10^-34 x 3.0 x 10^8 / 5.9 x 10^-7= 3.37x10-19 J Finally, the work function can be found by subtracting the kinetic energy from the energy provided by the photon to give: W.F.= (3.37-1.14)x10^-19= 2.23x10^-19 J

BJ
Answered by Bevan J. Physics tutor

2359 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

Name an experiment proving that light is wave and one that is proving that light consists of particles.


An electron is moving with speed 2x10^5ms-1 through a magnetic field of strength 0.5T. If the electrons velocity is perpendicular to the direction of the magnetic field, what is the magnitude of the force felt by the electron?


Calculate the threshold wavelength for a metal surface with work function of 6.2 eV.


What is the gravitational force between two steel spheres of radius 10 meters and density 8000 kilograms per meter cubed


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