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Dual Nature Of Radiation And Matter
the threshold frequency for a certain metal is 3 3...

Question:
The threshold frequency for a certain metal is 3.3 × 10¹⁴ Hz. If light of frequency 8.2×10¹⁴ Hz is incident on the metal, predict the cut-off voltage for the photoelectric emission.

Answer:

Threshold frequency of the metal, V₀ = 3.3 x 10¹⁴ Hz

Frequency of light incident on the metal, V = 8.2 x 10¹⁴ Hz

Charge on an electron, e = 1.6 × 10⁻¹⁹ C

Planck’s constant, h = 6.626 × 10⁻³⁴ Js

Cut-off voltage for the photoelectric emission from the metal = V₀

The equation for the cut-off energy is given as: eV₀ = h (v - v₀)

∴ v₀ = h(v - v₀) / e = 6.626 x 10^-34 x (8.2 x 10¹⁴ - 3.3 x 10¹⁴) / 1.6 x 10-19 = 2.0292 V

Therefore, the cut-off voltage for the photoelectric emission is 2.0292 V

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Question:
The threshold frequency for a certain metal is 3.3 × 10¹⁴ Hz. If light of frequency 8.2×10¹⁴ Hz is incident on the metal, predict the cut-off voltage for the photoelectric emission.

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Question: The threshold frequency for a certain metal is 3.3 × 1014 Hz. If light of frequency 8.2×1014 Hz is incident on the metal, predict the cut-off voltage for the photoelectric emission.

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Question:
The threshold frequency for a certain metal is 3.3 × 10¹⁴ Hz. If light of frequency 8.2×10¹⁴ Hz is incident on the metal, predict the cut-off voltage for the photoelectric emission.