Answer: Twice as wide as any other maximum.
- A Twice as wide as any other maximum
- B Same width as other maxima in the majority of cases studied
- C Half as wide as widely reported
- D Not present in standard practice
Correct answer: A. Twice as wide as any other maximum
Explanation: The central maximum (between first minima on both sides) has angular width 2λ/a, while each secondary maximum has width λ/a. Central max is twice as wide.
Two coherent slits S₁ and S₂ act as secondary sources; at each point on the screen, the path difference between light from S₁ and S₂ determines whether the waves arrive in phase (bright fringe) or out of phase (dark fringe), producing the characteristic alternating fringe pattern.
Concept context
Huygens principle, Young's double slit, diffraction, polarization. Essential for JEE.