Explain why centripetal acceleration changes the direction of velocity in circular motion but not its magnitude.
Thomas 1 Trigonometry Example: Pythagorean Theorem: Scalars & Vectors Scalar quantities are just a number 1. Examples: a. Temperature b. Height c. Mass 2. Note that scaler quantities exclude physical quantities Vector Quantities 1. Vectors are described by magnitude and direction arrows. a. The arrows indicate the direction of the vector. b. Vectors can be used to describe forces, acceleration, and velocity. c. R vectors is proportional to the magnitude of the vector. Vector Addition 1. Consider magnitude and direction while using these. 2. All vectors as seen on a diagram should be attached head to tail unless it is the R vector. Example 1: Find the magnitude and direction of R using addition when A is 275m East and B is 125m North. A. Add A and B: R = A + B → R = 275m + 125m → 400 m B. To solve for magnitude of R: R = |R| = +R = √A + 2 →R = 27√ + 125 = 302 m C. To solve for R’s direction: (Tip: Use the Trig equation that best suits the problem.) Thomas 2 125 tan∅ = → ∅ = tan −1 → tan −1 = 26.6○ 275 Components of Vectors 1. When you can’t use the Pythagorean theore
