Aim How do we solve vector problems graphically
Aim: How do we solve vector problems graphically? Do Now: Quiz HW: Problem Set
How do we describe vectors? • Vectors have magnitude and direction. Examples: Displacement, velocity, force, acceleration & momentum. • Scalars have only magnitude • Vectors are drawn as arrows ALWAYS! • We can use vectors to calculate the resultant or sum of vectors.
Equilibrium Force • Only forces! • Equal and opposite the resultant! Two ropes are tied to a fence at the same point. Taylor pulls East with a force and Jeff pulls 30 degrees South East with a force. 1. Draw the resultant 2. Draw the equilibrium Force
Measuring Angles Draw an angle that is 40 o West of North Draw an angle that is 130 o North of East Draw an angle that is 140 o West of South Do you notice anything? ? ? • All these directions are the same!
How to Solve Graphically Vectors in 2 -D: 1. Define your scale 2. Draw your vectors using the tip-to-tail method. 3. Draw the resultant vector. 4. Measure the vector and the angle. 5. Describe the direction in terms of degrees and direction (N, N of E, W, W of S, etc)
Vector Activity Use the protractor to calculate the resultant vector in each of the following problems: 1. A person walks 5. 0 meters east and 12. 0 meters at 60 degrees north of east. Find the magnitude and direction of the resultant displacement. (15 m@43 deg. ) 1. A boat moves with a velocity of 2 m/s North when it encounters a gust of wind with a velocity of 2 m/s west. What is the resultant velocity of the boat? (Include the angle)
Final Question You are running to physics class because you just can’t wait to get there and learn more about vectors! To get to class, you run 3 m North, 5 m West, and 1 m, 40 O Southeast. 1) What was the total distance you travelled? 2) What was your displacement from start to finish? Include the angle and direction in your answer.
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