THIS MINI-LESSON WILL COVER:What is the difference between scalars and

vector quantities?

What is the difference between distance and displacement ?

How can vectors be added or subtracted to show final direction?

What are scalars?Scalars are quantities that only

have magnitude (size).

Ex: Temperature

What are Vectors?Vectors are quantities that have both

magnitude (size) and direction.Ex: Force – you push something with a

certain amount of force (magnitude) in a particular direction.

Vectors can be represented by an arrow.

The length of the arrow represents the

magnitude and the arrow points in the direction.

Man, this vector quantity is hard work.

Force

Practice: Work with your partners to sort the following quantities into scalars and vectors.

DistanceDisplacementVelocitySpeedEnergyAcceleration

TimeNumber of fish in a

pondForceTemperature MomentumMass

AnswersSCALARS

DistanceSpeedEnergyMassTime

Number of fish in pondTemperature

VECTORS

DisplacementVelocity

AccelerationMomentum

Force

Day 2: Distance vs. DisplacementDistance: - The actual path of an object.

Displacement – the change in position. It gives the straight line distance from where you start to where you end. An x is usually used the symbol for

displacement .

displacement = final position – initial position

x = xf - xi

33

Solve the problem 1) The straight line

distance from a student’s house to school is 2 kilometers. If the student walks 2 kilometers to his friends house first and then 2 kilometers to school, what was the total distance traveled? What was his displacement?

Answer: distance = 4 kmdisplacement = 2 km

North(Don’t forget direction)

2 km

2 km

2 km

Solve the problem2) The space shuttle

takes off from Florida and circles the Earth 10 times before landing back in Florida. If one orbit is 41 thousand kilometers, what was the shuttles distance travelled? What was its displacement?

Answer: distance = 410,000 kmDisplacement = 0 km

Day 3: Vector AdditionVectors are helpful because they can be added to find both

final magnitude and final direction.Ex. A person walks west for 10 km and stops. After an hour they

walk another 15 km west. What was his final displacement?

To solve, use vector addition.

10 km, west 15 km, west

x = 10 km + 15 km = 25 km west

Vector addition cont…Ex. 2) A person walks 10 km west, turns

around, and then walks 15 km east. What is her displacement? Try to solve on your own.

10 km, west

15 km, east

X = 15 km – 10 km = 5 km, east

Vector addition cont.A person walks 100 m south and then 100 m

west. What was his final direction? Try to solve on your own.

Answer: Southwest

***Quiz: Tomorrow

Day 4 Quiz!