1. Vectors & Scalars Chapter 5.1-5.3 Notes

2. Vectors vs. Scalars A quantity that requires both magnitude (a numerical value) and direction is a vector Displacement, velocity, acceleration, and momentum are all vectors Examples: 10 miles north, 60 miles per hour east An arrow is used to show the direction of the vector; the length of the vector should be drawn to scale A quantity that can be described with only a magnitude is a scalar quantity Distance and speed are scalars Examples: 1 kg of cement, 5 liters of water There is no direction

3. Velocity Vectors An object’s velocity is often the result of combining two or more other velocities For example, an airplane’s velocity is a combination of the velocity of the airplane relative to the air and the velocity of the air relative to the ground A small plane may be flying north at 80 km/h, and a tailwind is blowing north at 20 km/h—since both the plane and the tailwind are in the same direction, the plane’s resultant velocity is 100 km/h north Suppose that instead of a tailwind, there is a headwind blowing 20 km/h south—what is the plane’s resultant velocity? 60 km/h

5. Parallel Vectors When vectors are parallel to one another, we can simply add or subtract the vectors to find the resultant vector Examples of adding vectors: 2 (or more) vectors to the right 2 vectors to the left 2 vectors downward, etc. Examples of subtracting vectors: 1 vector to the right and 1 to the left 1 vector upward and 1 vector downward, etc.

6. Perpendicular Vectors

8. Components of Vectors Sometimes a single vector needs to be changed into an equivalent set of two component vectors that are at right angles to each other Any vector can be “resolved” into two component vectors at right angles Components: two vectors at right angles that add up to a given vector Resolution: the process of determining the components of a vector The perpendicular components of a vector are independent of each other

9. Determining the Components Vector V represents a vector quantity First, horizontal and vertical lines are drawn from the tail of the vector Second, a rectangle is drawn that encloses the vector V The sides of the rectangle are the desired components, vectors X and Y

10. Classwork Pg 80, Define the 3 Key Terms Pg 81, #1-5 Pg 83, #18-21