I am very confused about angular velocity ω and why its used in simple harmonic motion. ω is described as θ/τ but when it comes to masses on springs, there is no angle - it is zero. Angular velocity comes from circular motion but the motion of SHM is not circular. My confusion is even greater when finding that in order to prove acceleration is directly proportional to displacement the equation is -ω^2x. I looked at how to prove this formula but couldn't understand it as I have no knowledge of calculus and derivatives. Anyways, I am just confused on why angular velocity is used in simple harmonic motion and how -ω^2x is representative of displacement. If my question does not make sense just let me know I'll be more than happy to clarify it. Thank you.