Relation between de-Broglie wavelength and K.E. is
λ=2(KE)meh⇒λ∝KE1
λBλA=KEAKEB
⇒21=TATA−1.5⇒TA=2eV
∴KEB=2−1.5=0.5eV
ϕB=4.5−0.5=4eV
JEE Main 2020 — Physics Modern Physics
When photon of energy 4.0eV strikes the surface of a metal A, the ejected photoelectrons have maximum kinetic energy TAeV and de-Broglie wavelength λA. The maximum kinetic energy of photoelectrons liberated from another metal B by photon of energy 4.50eV is TB=(TA−1.5)eV. If the de-Broglie wavelength of these photoelectrons λB=2λA, then the work function of metal B is:
Held on 8 Jan 2020 · Verified 6 Jul 2026.
4eV
2eV
1.5eV
3eV
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