Anyone know how to go about solving the following two problems?(adsbygoogle = window.adsbygoogle || []).push({});

- What is the minimum frequency photons need to knock an electron out of a copper target?

- If a beam of photons with 3 times the frequency of the photons from the first problem strikes a copper target, at what speed will the fastest electrons leave the copper?

Thank you.

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# Homework Help: Modern physics - photon problems

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