Arrange the following in a sequential order for the experimental study of photoelectric effect:
A. Emission of electrons from the plate takes place.
B. Monochromatic light of sufficiently short wavelength is incident on the plate.
C. A photosensitive plate is selected.
D. Electrons move towards the collector plate at positive potential.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → C, B, A, D
The photoelectric effect needs a photosensitive surface and light above its threshold frequency; the emitted electrons are then collected to give a photocurrent.
C — A photosensitive plate is selected.
B — Monochromatic light of sufficiently short wavelength is incident on the plate (its frequency is above the threshold).
A — Emission of electrons from the plate takes place.
D — Electrons move towards the collector plate at positive potential, so a photocurrent flows.
So the order is C, B, A, D.
NCERT (2026-27):
Experimental Study of Photoelectric Effect – “Figure 11.1 depicts a schematic view of the arrangement used for the experimental study of the photoelectric effect. It consists of an evacuated glass/quartz tube having a thin photosensitive plate C and another metal plate A. Monochromatic light from the source S of sufficiently short wavelength passes through the window W and falls on the photosensitive plate C (emitter). … The electrons are emitted by the plate C and are collected by the plate A (collector), by the electric field created by the battery.”