Threshold frequency is 3.3 × 10¹⁴ Hz. Light of frequency 8.2 × 10¹⁴ Hz is incident. Cutoff voltage is nearest:
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Threshold frequency is 3.3 × 10¹⁴ Hz. Light of frequency 8.2 × 10¹⁴ Hz is incident. Cutoff voltage is nearest:

G1 Physics · Accepted Answer

ν − ν₀ = (8.2 − 3.3) × 10¹⁴ = 4.9 × 10¹⁴ Hz. eV₀ = hΔν gives V₀ = 6.626 × 10⁻³⁴ × 4.9 × 10¹⁴/(1.602 × 10⁻¹⁹) ≈ 2.03 V. Answer: A.