What is speed?

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Speed, Velocity, and Acceleration: TEKS 8.6B
To the teacher:
• This CPO Science PowerPoint presentation is designed to guide you
through the process of presenting the lesson to your students. The
presentation uses a 5-E teaching model: Engage, Explore, Explain,
Elaborate, and Evaluate.
• The PowerPoint Slide notes indicate where you may want to bring in
various lesson elements such as quizzes, readings, investigations,
animations, and practice materials. Additional science background
information is provided in the slide notes where appropriate. You
can view these notes by selecting “View,” then “Normal.” You will
see the notes pane at the bottom of the PowerPoint workspace.
Additionally, the slide notes are available as a separate document,
accessible from the lesson home page.
• The slides that follow are intended for classroom use.
Speed, Velocity, and Acceleration: TEKS 8.6B
Describing motion
• It’s a fact: You are always in
motion, even when you are fast
asleep.
• How can this be? Can you give
any examples to support this
statement?
Speed, Velocity, and Acceleration: TEKS 8.6B
What is speed?
• Speed is distance traveled divided by time taken.
Distance traveled
Speed 
Time taken
• What is the girl’s average speed if she crosses the
finish line in 15 seconds?
Speed, Velocity, and Acceleration: TEKS 8.6B
What is velocity?
• The velocity of an object tells you both its speed and
its direction of motion.
• The velocity of an object changes when its direction
changes as well as when its speed changes.
• Velocity can be positive or negative. If the velocity is
negative, the object is moving toward the origin.
• Which car in the graphic has a negative velocity?
Speed, Velocity, and Acceleration: TEKS 8.6B
What is acceleration?
• Acceleration is the change in velocity over time.
• Acceleration changes when the object’s speed
changes and/or when the object’s direction changes.
• An object traveling at a constant speed in one
direction has an acceleration of zero.
• Acceleration is negative if the object is slowing down.
Speed, Velocity, and Acceleration: TEKS 8.6B
Try this:
• A rabbit starts from a resting position
and moves at 6 m/s after 3 seconds.
What is the acceleration
of the rabbit?
Speed, Velocity, and Acceleration: TEKS 8.6B
Time to investigate!
• Complete the lesson investigation:
- Acceleration: How is the speed of the car changing?
Speed, Velocity, and Acceleration: TEKS 8.6B
Time for Practice!
• Complete the lesson practice activity.
Look over the examples and then try this first problem with a partner.
Speed, Velocity, and Acceleration: TEKS 8.6B
Show what you know!
• Try the lesson’s interactive quiz,
or complete a quiz that your
teacher can print out for you.
• Hint:
– You might want to review your
lesson reading piece one more time
before trying the quiz.
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