Question: User: Scene 8: Practice Problem - Two Sources with λ = 3 cm Visual Prompt for AI Video Generator: Prompt: Animated graphic display of two in-phase sources S1 and S2 separated by 9 cm, producing waves with wavelength λ = 3 cm[cite: 15]. Wavefront arcs expand[cite: 15]. Point A and Point B are highlighted on the wave grid[cite: 15]. Step-by-step whiteboard calculation overlay solves: 1) Path difference for Point A and B[cite: 15]. 2) Counting nodal lines between S1 and S2[cite: 15]. Part B calculation: S1P = 30 cm, S2P = 37.5 cm, Δd = 7.5 cm = 3*(λ/2)[cite: 15]. Displays zero amplitude for in-phase sources, and max amplitude 2.0 cm when switched to antiphase[cite: 15]. English Voiceover & Text: Voiceover: "Let's test our knowledge! For waves with a 5.0-centimeter wavelength and paths of 30 and 37.5 centimeters, the path difference is 7.5 centimeters—exactly 3 half-wavelengths[cite: 15]. In phase, this yields total cancellation with 0 amplitude; in antiphase, it turns into constructive interference with a full 2.0-centimeter amplitude[cite: 15]!"