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Question
Photons of wavelength λ are incident on a metal. The most energetic electrons ejected from the metal are bent into a circular arc of radius R by a perpendicular magnetic field having magnitude B. The work function of the metal is
Options
`"hc"/λ - "m"_"e" + ("e"^2"B"^2"R"^2)/(2"m"_"e")`
`"hc"/λ + 2"m"_"e" ["eBR"/(2"m"_"e")]^2`
`"hc"/λ - "m"_"e""c"^2 - ("e"^2"B"^2"R"^2)/(2"m"_"e")`
`"hc"/λ - 2"m"_"e" ["eBR"/(2"m"_"e")]^2`
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Solution
`"hc"/λ - 2"m"_"e" ["eBR"/(2"m"_"e")]^2`
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