Curves of constructive and destructive interference from two point sources
This is an expanded and refined applet compared to my earlier applet.
Waves from two coherent, spatially separated sources of oscillations interfere in such a way that the oscillations are amplified in some directions in space (constructive interference: antinodes of lines or maximum intensity) and completely weakened in some directions (destructive interference: nodal lines or minimum intensity). Examples are water waves, sound waves, light waves ... .
This applet allows you to visualize and study this phenomenon. You can change the distance b between the sources, as well as the wavelength λ. In these cases, the selected interference lines (actually curves) are hyperbolas. The resulting hyperbolic interference lines are mathematically modeled taking into account the principle that the path difference Δ must be less than the distance b between the sources. If Δ≥b, the triangle inequality would be violated, making it physically impossible to find a point that satisfies this condition and therefore rendering interference impossible.
The following applet can be used to explore the features of constructive and destructive interference from two point sources in the "near" and "far" fields.