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3 years ago

Find the least frequency of incident light that will knock electrons out of the surface of a metal with a work function of 3eV.

Physics

1 answer:

mixer [17]3 years ago

3 0

Answer:

The frequency must be: $725\,\,10^{12} \,Hz$

Explanation:

If the work function of the metal ( $\phi$ ) is 3 eV, then we can use the formula for the kinetic energy of an ejected electron:

$KE= h*f-\phi$

considering for the minimum KE = 0, and using the Plank constant h in eV s as: 4.14 * 10 ^(-15) eV s, to solve for the frequency:

$h*f=\phi\\4.14*10^{-15} * f = 3\\f=3*10^{15} /4.14\,\,\frac{1}{s} \\f=725\,10^{12} \,Hz$

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Answer:

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4 years ago

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julia-pushkina [17]

Answer:

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3 years ago

Find the least frequency of incident light that will knock electrons out of the surface of a metal with a work function of 3eV.​

Find the least frequency of incident light that will knock electrons out of the surface of a metal with a work function of 3eV.