B=B0[sin(3.14×107ct)+sin(6.28×107ct)]
Maximum KE will associate with the maximum frequency
fmax=2π6.28×107c=107×3×108Hz=3×1015Hz
KEmax=hfmax−ϕ
=[1.6×10−196.63×10−34×3×1015−4.7eV]
=7.72eV
The magnetic field associated with a light wave is given, at the origin, by B=B0[sin(3.14×107)ct+sin(6.28×107)ct]. If this light falls on a silver plate having a work function of 4.7eV, what will be the maximum kinetic energy of the photoelectrons?
(c=3×108ms−1,h=6.6×10−34Js)
Held on 9 Jan 2019 · Verified 6 Jul 2026.
6.82eV
7.72eV
12.5eV
8.52eV
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