Enter amplitude, phase (rad), period T (seconds), and harmonic n (integer ≥ 1). View shows one rotating phasor and its sine; Add appends to the chain: each circle’s center sits at the tip of the previous vector. The right plot is y(t) = Σ Ak sin(ωkt + φk), with ωk = nk·2π/Tk (same T and n makes every arm spin at the same rate—use n = 1, 2, 3… for harmonics).