λ0=3250×10−10m
λ=2536×10−10m
ϕ=λ0hc=325nm1242eV−nm=3.82eV
hν=λhc=253.6nm1242eV−nm=4.89eV
By Einstein’s photoelectric equation
Kmax=λhc− λ0hc
KEmax=(4.89−3.82)eV=1.07eV
21mv2=1.07×1.6×10−19
v=9.1×10−312×1.07×1.6×10−19
v=0.6×106m/s
The photoelectric threshold wavelength of silver is 3250×10–10m. The velocity of the electron ejected from a silver surface by ultraviolet light of wavelength 2536×10–10m is:-
(Givenh=4.14×10−15eVsandc=3×108ms−1)
Held on 30 Apr 2017 · Verified 9 Jul 2026.
≈6×106ms−1
≈0.6×106ms−1
≈61×103ms−1
≈0.3×106ms−1
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