1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Relationship between λ and max kinetic energy

  1. Oct 3, 2014 #1
    1. The problem statement, all variables and given/known data
    When lights falls on metal suface , electrons are emitted if the wavelength of light is less than or equal to λ , .If lights of 0.5λ is used , then maximum kinetic energy of electrons is E . if lights of 0.25λ is used , what's the maximum kinetic energy of the electron emitted?
    the ans is 3E... why?
    2. Relevant equations

    3. The attempt at a solution
    since E is inversely propotional to λ , so my ans is 2E ....
  2. jcsd
  3. Oct 4, 2014 #2


    User Avatar

    Staff: Mentor

    3E is correct. Show your working in full.

    Note carefully that E is defined as max KE at a particular λ .
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted