Question

Condition of diffraction is:

• A. $\frac{a}{\lambda }=1$
• B. $\frac{a}{\lambda }>>1$
• C. $\frac{a}{\lambda }<<1$
• D. None of these

Answer 1

Answer: (A)

If size of obstacle is equal to wavelength of light then diffraction pattern occurs
$a\approx \lambda$
$\Rightarrow \frac{a}{\lambda }\approx 1$