Light of incident frequency 3 times the threshold frequency is incident on a photosensitive material. If the incident frequency is made (1/4) th and intensity is tripled then the photoelectric current will (a) increase. (b) decrease. (c) be (1/3) rd (d) be zero.

Answer: (d). ν = 3ν₀; new frequency ν' = (3ν₀)/(4) = 0.75ν₀ < ν₀. Below threshold no photoelectrons are emitted, whatever the intensity. So the answer is (d) be zero.

Light of incident frequency 3 times the threshold frequency is… | MHT CET 2025 (26 Apr, Shift 1)

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Photoelectric Experiment: Intensity, Stopping Potential & Graphs

Light of incident frequency 3 times the threshold frequency is incident on a photosensitive material. If the incident frequency is made $\left(\frac{1}{4}\right)$ th and intensity is tripled then the photoelectric current will

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Answer: (d)

$\nu = 3\nu_0$ ; new frequency $\nu' = \frac{3\nu_0}{4} = 0.75\nu_0 < \nu_0$ .
Below threshold no photoelectrons are emitted, whatever the intensity.
So the answer is (d) be zero.

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