The cathode of a photoelectric cell is changed such that the work function changes from W₁ to W₂ ( W₂ > W₁). If the current before and after changes are I₁ and I₂, all other conditions remaining unchanged, then (assuming hν > W₂) (a) I₁ = I₂ (b) I₁ I₂ (d) I₁ < I₂ < 2I₁

Answer: (a). Photocurrent ∝ number of photons per second (intensity), as long as hν > W. Changing W changes only the kinetic energy of the electrons, not their number. So the answer is (a) I₁ = I₂.

The cathode of a photoelectric cell is changed such that the work… | NEET 1992 (AIPMT)

Q87NEET 1992 · AIPMTMedium

Photoelectric Experiment: Intensity, Stopping Potential & Graphs

The cathode of a photoelectric cell is changed such that the work function changes from $W_1$ to $W_2$ ( $W_2 > W_1$ ). If the current before and after changes are $I_1$ and $I_2$ , all other conditions remaining unchanged, then (assuming $h\nu > W_2$ )

Show answer and solution

Answer: (a)

Photocurrent $\propto$ number of photons per second (intensity), as long as $h\nu > W$ .
Changing $W$ changes only the kinetic energy of the electrons, not their number.
So the answer is (a) $I_1 = I_2$ .

Report a mistake

Photoelectric Experiment: Intensity, Stopping Potential & Graphs question from NEET 1992 (AIPMT)

More questions on Photoelectric Experiment: Intensity, Stopping Potential & Graphs