Relationship between λ and max kinetic energy

AI Thread Summary
When light strikes a metal surface, electrons are emitted if the wavelength is less than or equal to a certain threshold, λ. The maximum kinetic energy (KE) of emitted electrons is directly related to the wavelength of the light used. For light at 0.5λ, the maximum KE is defined as E, while using light at 0.25λ results in a maximum KE of 3E. This is because the energy of the emitted electrons increases as the wavelength decreases, following the relationship that energy is inversely proportional to wavelength. Thus, the correct maximum kinetic energy for light at 0.25λ is indeed 3E.
desmond iking
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Homework Statement


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?

Homework Equations

The Attempt at a Solution


since E is inversely propotional to λ , so my ans is 2E ...[/B]
 
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3E is correct. Show your working in full.

Note carefully that E is defined as max KE at a particular λ .
 

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