Activity 82 Major Concepts• Friction is a force that will cause changes

in the speed of an object’s motion.

• The motion of an object can be described by it position, direction of motion, and speed.

Activity 83 Analysis1. Why does stopping distance depend on

road conditions?

• friction

• road conditions affect friction

• surfaces with less friction are more slippery.

2. What might cause:

a. Slippery road conditions?

• snow, ice, gravel, and oil

b. driver distractions?• cell phone, music, passengers, eating, and other

vehicles3. In which of the three situations (alert and dry,

alert and slippery, or distracted, or distracted and dry) does it take:

a. the least distance to stop? Explain using evidence.

• Explain using your evidenceb. 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:

a. 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……

b. on a wet road? Show your evidence.

5. Would your answers to Analysis Question 4 change if:

a. 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……

b) You were driving 20 MPH instead of 40 MPH? Explain

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

Read E-49

Activity 84

Title: Decelerating Safely

Problem: How can a person’s deceleration be controlled during a collision?

Hypothesis: If _____, then __________.

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.

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.

Data/Observations:

• Talking Drawing: Safety Features• Before reading:

• After reading:

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.

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)

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.

Do Analysis Questions 1-4