Light source having wavelength 331 nm is used to generate photo-electrons whose stopping potential is 0.2 V. The work function of the used metal in the experiment is α×10−19 J. The value of α is _____.
(h=6.62×10−34 J s, e=1.6×10−19 C and c=3×108 m/s)
Held on 5 Apr 2026 · Verified 6 Jul 2026.
3.68
4.68
5.68
2.68
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