The minimum frequency of light needed to eject electrons from a metal is called the threshold frequency, 0 . Find the minimum energy needed to eject electrons from a metal with a threshold frequency of 2.47×1014 s−1. g

E = 0.965eV

Explanation:

In order to calculate the minimum energy needed to eject the electrons you use the following formula:

       (1)

h: Planck' constant = 6.626*10^{-34}J.s

v: threshold frequency = 2.47*10^14 s^-1

You replace the values of v and h in the equation (1):

In electron volts you obtain:

The minimum energy needed is 0.965eV

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