Question

What path difference produces constructive interference?

Options

• \[\Delta x=n\lambda\]

• \[\Delta x=2n\pi\]

• \[\Delta x=(2n+1)\pi\]

• \[\Delta x=\left(n+\frac{1}{2}\right)\lambda\]

Answer 1

Constructive interference occurs when the path difference is \[\Delta x=n\lambda\]. Here, \[n=0,1,2,3,\ldots\], so the path difference is a whole-number multiple of the wavelength.