Chad provides a review of springs and a brief review of trigonometry in preparation for the next lesson on simple harmonic motion. The review of springs focuses on Hooke's Law, elastic potential energy, and the conservation of mechanical energy. When a spring is undergoing simple harmonic motion, the instantaneous force and acceleration and the elastic potential energy will be zero at the equilibrium position (when the displacement is zero) while the kinetic energy and velocity will reach their maximums. When the mass on the spring reaches is maximum displacement, the kinetic energy and instantaneous velocity will be zero, while the instantaneous force and acceleration and the elastic potential energy reach their maximums.
The position, velocity, and acceleration of an object undergoing simple harmonic motion are modeled with sine and cosine functions, so Chad spends a little time reviewing them. He compares cos x with 2cos x and sin x with 2sin x showing how the coefficient affects the amplitude. He then compares cos x with cos 2x and sin x with sin 2x showing how this affects the period of the sine and cosine functions.
00:00 Lesson Introduction
00:38 Review of Springs, Hooke's Law, and Elastic PE
07:06 Trigonometry Review: Cosine Functions
13:43 Trigonometry Review: Sine Functions
Check out Chad's General Physics Master Course: www.chadsprep.com/physics-youtube
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