For a metal with cutoff frequency ν₀, radiation of frequency 2ν₀ strikes the surface. Maximum speed of electrons (mass m) is:
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For a metal with cutoff frequency ν₀, radiation of frequency 2ν₀ strikes the surface. Maximum speed of electrons (mass m) is:

G1 Physics · Accepted Answer

Einstein equation gives Kₘₐₓ = h(2ν₀ − ν₀) = hν₀. Thus ½mv² = hν₀ ⇒ v = √(2hν₀/m). Answer: C.