Two monochromatic and coherent point sources of light are placed at a certain distance from each other in the horizontal plane. The locus of all those points in the horizontal plane which have constructive interference will be
Options

Question

Two monochromatic and coherent point sources of light are placed at a certain distance from each other in the horizontal plane. The locus of all those points in the horizontal plane which have constructive interference will be

Options

G1 Physics · Accepted Answer

Constructive interference requires path difference r₁−r₂=mλ. The locus of constant difference of distances from two fixed points is a hyperbola; varying integer m gives a family of hyperbolas. Hence option B.