Scalar A scalar quantity has magnitude size only

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Scalar: A scalar quantity has magnitude (size) only, but no direction. Examples include: time,

Scalar: A scalar quantity has magnitude (size) only, but no direction. Examples include: time, mass, distance and speed. Vector: A vector quantity has both magnitude and direction. Examples include: displacement, velocity and force.

The position of an object is the separation between that object and a reference

The position of an object is the separation between that object and a reference point. (which is usually “zero” on the scale) The position of car B is 1. 0 m to the left of the reference. The position of car A is 8. 0 m to the right of the reference. Since we stated the direction, position is a VECTOR quantity.

Distance, on the other hand, needs no frame of reference. You measure the distance

Distance, on the other hand, needs no frame of reference. You measure the distance between two objects by measuring their separation. Car A is 9. 0 m from car B no matter where you put the reference point. Since we did not state the direction, distance is a SCALAR quantity.

5. 0 m The displacement of an object is defined as its change in

5. 0 m The displacement of an object is defined as its change in position, relative to where it started. The car has moved a distance of 5. 0 m. The displacement of the car is 5. 0 m to the right. Since we stated the direction, displacement is a VECTOR quantity.

When using vector quantities in formulas, we do not write the directions using words.

When using vector quantities in formulas, we do not write the directions using words. Instead, we use positive (+) and negative (-) signs. positive directions forward up right east north negative directions backward down left west south

X-Axis Method How to use the X-axis Method: Up (90 o) Left (180 o)

X-Axis Method How to use the X-axis Method: Up (90 o) Left (180 o) 40 o Right (0 o) Read the grid from 0 o counterclockwise and include direction. • Up and right are positive 5 m • Down and left are negative Down (270 o) • Directions between axis lines are given only in degrees. For Example: Vector A is positioned at 5 m (220 o) See page 139, example problem B 1. 4 for more examples.

Navigator Method How to use the Navigator Method: N (0 o) W (270 o)

Navigator Method How to use the Navigator Method: N (0 o) W (270 o) 40 o Read the grid from 0 o clockwise and include direction. E (90 o) • North and east are positive • South and west are negative 5 m S (180 o) • Directions between axis lines are given only in degrees. For Example: Vector A is positioned at 5 m (230 o) See page 140, example problem B 1. 5 for more examples.

Navigator II Method (‘of’ Method)

Navigator II Method (‘of’ Method)

t = 1. 2 s 5. 0 m The car has a displacement of

t = 1. 2 s 5. 0 m The car has a displacement of 5. 0 m to the right in 1. 2 s. The average velocity of the car is defined as a change in position during a time interval. It is called an average velocity because it does not take into account speeding up and slowing down. = average velocity (m/s) = displacement (m) Δt = time (s) We use the arrows “→” to indicate vector quantities.

t = 1. 2 s 5. 0 m Remember to state the direction with

t = 1. 2 s 5. 0 m Remember to state the direction with vector quantities! = 4. 2 m/s to the right Since we stated the direction, average velocity is a VECTOR quantity.

Practice Problems p. 141 8) A student walks 10. 0 m [E] in 7.

Practice Problems p. 141 8) A student walks 10. 0 m [E] in 7. 00 s. Then he walks another 12. 0 m [E] in 8. 00 s. Determine: a) the displacement of the student in 15. 00 s b) the average velocity of the student. 22. 0 m [E] 1. 47 m/s [E] 9) A boat travels at a velocity of 8. 00 m/s [N] for 14. 0 s. What is the displacement of the boat? 112 m [N] 10) An airplane flying at a velocity of 900 km/h [W] travels 400 km west. How long will the plane be in flight? 0. 444 h

Jonny walks 10 m [N] and then turns and heads east for 15 m.

Jonny walks 10 m [N] and then turns and heads east for 15 m. What is Jonny’s total displacement Adding Vectors

The only difference between distance-time graphs and position-time graphs is that direction is included.

The only difference between distance-time graphs and position-time graphs is that direction is included. This means that the slope is equal to the velocity.

ü read pages 137 – 144 ü Line master 3 – Graphical analysis if

ü read pages 137 – 144 ü Line master 3 – Graphical analysis if uniform motion (average velocity) ü B 1. 1 Check and Reflect page 145 #’s 1 -7