In a Young’s double slit experiment, the intensity of central maxima is \( I \). If we cover one of the slits, the intensity of central maxima would become
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → \( I/4 \)
In Young’s experiment the waves from the two slits are coherent, so their amplitudes add at the central maximum, and intensity is proportional to the square of the amplitude.
With each slit alone giving amplitude \( a \) and intensity \( I_{0} \propto a^{2} \):
\( \text{Both slits: } I \propto (2a)^{2} = 4a^{2} \ \Rightarrow\ I = 4I_{0} \)
\( \text{One slit covered: } I' = I_{0} = I/4 \)