Activity 82 Major Concepts

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Activity 82 Major Concepts

• Friction is a force that will cause changes in
  the speed of an objects motion.
• The motion of an object can be described by it
  position, direction of motion, and speed.

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Activity 83 Analysis

• Why does stopping distance depend on road
  conditions?
• friction
• road conditions affect friction
• surfaces with less friction are more slippery.
• What might cause
• Slippery road conditions?
• snow, ice, gravel, and oil

3

• driver distractions?
• cell phone, music, passengers, eating, and other
  vehicles
• In which of the three situations (alert and dry,
  alert and slippery, or distracted, or distracted
  and dry) does it take
• the least distance to stop? Explain using
  evidence.
• Explain using your evidence
• the most distance to stop? Explain using
  evidence.
• This depends on driving speed. At speeds of ____
  or less, ______________. At speed greater than
  ____, the stopping distance for....

4

• You are alertly driving a car at 40 MPH (18 m/s).
  You come around a bend and see that a tree has
  fallen across the road 50 meters away. Will you
  be able to top before you hit the tree
• on a dry road? Show your evidence.
• At 40 MPH, it takes __meters for an alert drive
  to stop car on dry pavement. Under these
  conditions my car would

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• on a wet road? Show your evidence.
• Would your answers to Analysis Question 4 change
  if
• something were distracting your attention as you
  came around the bend? Explain.
• If I were distracted, it would take __ meters to
  stop in dry conditions, and
• You were driving 20 MPH instead of 40 MPH? Explain

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Activity 83 Major Concepts

• Stopping distance is the sum of reaction time and
  braking distance
• There are many factors which affect stopping
  distance (list some)
• The potential for accidents and the existence of
  hazards impose the need for injury prevention

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Read E-49
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Activity 84

• Title Decelerating Safely
• Problem How can a persons deceleration be
  controlled during a collision?
• Hypothesis If _____, then __________.

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How do you know when you are accelerating while
traveling in a car?

• Starting up from a stoplight.
• Passing a vehicle.
• Acceleration is happening when you have the
  feeling of being pushed back in the seat while
  the car accelerates forward.

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How do you know when you are decelerating while
traveling in a car?

• When a car comes to a stop, it will make
  passengers feel like they are thrown forward as
  the car decelerates.

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Data/Observations

• Talking Drawing Safety Features
• Before reading
• After reading

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Talking Drawing Safety Features

• Before reading
• Close your eyes and think about what a safe
  vehicle looks like. Now, open your eyes and draw
  what you imagined. Label any parts of the vehicle
  that have special features.

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Three Level Reading Guide

• Read the statements on Student Sheet 84.2 before
  you do the reading
• As you read, check the statements that are
  correct (supported by the text).
• In the third section, check the statements you
  agree with. Support each statement (whether you
  agree or not) with ideas from the reading and
  your own knowledge. Actually write it down
  (ignore the instructions on the sheet)

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Talking Drawing After reading

• Redraw your safe car with added safety features
  that you read about.
• Below the 2nd drawing, write a brief paragraph
  about what you changed from your original drawing.

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Do Analysis Questions 1-4