If I0 is the intensity of the principal maximum in the single slit diffraction pattern, then what will be its intensity when the slit width is doubled ?

Question

If I0 is the intensity of the principal maximum in the single slit diffraction pattern, then what will be its intensity when the slit width is doubled ? (A) 2I0 (B) 4I0 (C) I0 (D) (I0/2)

Tardigrade Admin · Accepted Answer

When the slit width is doubled the energy falling per sec on the screen is doubled but angular width of central maxima (Δ θ=(2 λ/ b )) is halved. Hence intensity of the central maxima will be 4 I 0.

Q. If $I_{0}$ is the intensity of the principal maximum in the single slit diffraction pattern, then what will be its intensity when the slit width is doubled ?

$2 I_{0}$

$4 I_{0}$

$I_{0}$

$\frac{I _{0}}{2}$

When the slit width is doubled the energy falling per sec on the screen is doubled but angular width of central maxima $(Δ θ = \frac{2 λ}{b})$ is halved. Hence intensity of the central maxima will be $4 I_{0}$ .

Q. If I0​ is the intensity of the principal maximum in the single slit diffraction pattern, then what will be its intensity when the slit width is doubled ?

2I0​

4I0​

I0​

2I0​​