All electrons ejected from a surface by incident light of wavelength 200 nm can be stopped before travelling 1 m in the direction of uniform electric field of 4N/C. The work function of the surface is –
Answer & explanation
Correct answer: option 4
$V_s = E.d$
$V_s = 4Volt$
$eV_s = \frac{12400}{λ}– W$
$4 eV =\frac{12400eV}{2000}– W$
4eV = 6.2eV – W
[W = 2.2 eV]