(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

What will be the electric charge of an isolated ball of copper, which was projected long enough with radiation of wavelength [tex]\lambda = 1400 \angstrom[/tex]?

2. Relevant equations

The radius of the ball is R=1cm and the work function of copper is [tex]\Phi = 4.47 eV[/tex].

3. The attempt at a solution

[tex]E_{k}^{max} = \frac{hc}{\lambda} - \Phi_{Cu}[/tex]

I want to say that the last electron which will be "released" will have kinetic energy that is equal to the potential energy on the surface of the ball.

The potential on the surface of the ball is Q/R, but how do I represent Q? Isn't it changes with the emission of the electrons?

Thanks.

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# Homework Help: Photoelectric Effect Problem

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