87.4 simple harmonic motion and the uniform circular motion >0 vKO KO 0 Simple harmonic motion can be described as the projection of a uniform circular motion along a diameter of the circle. A is called rotating vector. 7. 4 simple harmonic motion and the uniform circular motion v(1) x(t)=Acos(@t+o) v(t)=- Ao sin(ot+φ)9 §7.4 simple harmonic motion and the uniform circular motion Simple harmonic motion can be described as the projection of a uniform circular motion along a diameter of the circle. A is called rotating vector. r A r ϕ π 2 3 = ϕ =π ϕ = 0 ϕ = π 2 0 0 < > v x 0 0 > > v x 0 0 > < v x 0 0 < < v x ω A r §7.4 simple harmonic motion and the uniform circular motion A ωA x(t) = Acos(ωt +φ ) v(t) = −Aω sin(ωt +φ )