Chapter 2, Lesson 3: Velocity

1

• Chapter 2, Lesson 3 Velocity
• Nov 9 12

Homework Due Math
Tonights HW Read and study 2.3 complete 6-8 on pg 25
Do Now You run a distance of 5 meters in 50 seconds. Your friend runs a distance of 6 meters in 1 minute who has the greater average speed? SHOW ALL WORK
2

• You can describe the motion of an object by its
  position, speed, direction, and acceleration.

3
Concept Attainmentplease take handout

• YES
• this box will contain examples that CORRECTLY
  show todays new concept

• NO
• this box will contain examples that DO NOT show
  todays new concept

Your job is to come up with a hypothesis that
describes the differences between the YES and NO
examples what they ARE/ ARE NOT what they have
in common, etc. You may work in small groups if
you would like. We will ask for
groups/individuals to volunteer their hypothesis.
4
Concept Attainment

• NO
• 50 km/h
• 25 m/s
• 10 km/h
• 20 m/s
• 15 m/s

• YES
• 50 km/h north
• 25 m/s south
• 10 km/h east
• 20 m/s west
• 15 m/s northeast

You MAY work with others. Come up with a
hypothesis that describes any of the following
the differences between the YES and NO examples
what they ARE/ ARE NOT what they have in common,
etc. Random individuals/groups will be called on
to share their hypothesis.
5
2.3
Now, lets share hypotheses

• BIG IDEA (write down in 2nd box)
• Speed is a description of how fast an object
  moves velocity is how fast and in what direction
  it moves.
• (Make note of this on Concept Attainment
  handout!)

6

• Which column lists examples of
• SPEED?
• VELOCITY?
• Label on your Concept Attainment handout

• YES
• 50 km/h north
• 25 m/s south
• 10 km/h east
• 20 m/s west
• 15 m/s northeast

• NO
• 50 km/h
• 25 m/s
• 10 km/h
• 20 m/s
• 15 m/s

7
2.3 Velocity

• In physics, velocity is speed in a given
  direction.
• When we say a car travels at 60 km/h, we are
  specifying its speed.
• When we say a car moves at 60 km/h to the north,
  we are specifying its velocity.
• Any questions about how you labeled your columns
  on your concept attainment sheet?

8
Vector vs. Scalar http//www.youtube.com/watch?v
ajTeseYcimE

• Vector magnitude (how much?) and direction

• Scalar magnitude only

• Is speed a SCALAR or VECTOR quantity?_______
• Is velocity a SCALAR or VECTOR quantity?_____

9
2.3 Velocity

• Is speed a SCALAR or VECTOR quantity?_____________
  
• Is velocity a SCALAR or VECTOR
  quantity?_____________

Scalar (s for speed/scalar)
Vector (v for velocity/vector)
10
2.3 Velocity

• Constant Velocity

• Constant speed means steady speed. Something
  with constant speed doesnt speed up or slow
  down.
• Constant velocity means both constant speed and
  constant direction.
• Constant direction is a straight line, so
  constant velocity means motion in a straight line
  at constant speed.

11

• Fill this in on notes

Constant Velocity Changing Velocity
To have constant velocity requires BOTH constant __________________________ and constant __________________________. If EITHER the __________________________ or __________________________ (or both) is changing, then the velocity is changing.
12

• Fill this in on notes

Constant Velocity Changing Velocity
To have constant velocity requires BOTH constant __________________________ and constant __________________________. If EITHER the __________________________ or __________________________ (or both) is changing, then the velocity is changing.
Speed
Speed
Direction
Direction
13

• Answer the rest of the questions in your Concept
  Attainment in lab groups
• (Check in at stop signs)
• Work efficiently!
• When you are done, you can finish your group
  activity from last class and turn in for
  INDIVIDUAL grades. You have until the end of
  class