Lesson #101
Total Distance
versus Displacement




Quote of the Day:

"We use only 10% of our brains ... Imagine how smart we would be if we used the other 60%!" -- Ellen DeGeneres



Objectives:

The student will distinguish between total distance and displacement.

The student will determine displacement and total distance traveled.



1. Collect Homework.

2. Distance problem

At 60 mph, it takes 60 seconds to travel a mile.
At 120 mph, it takes 30 seconds to travel a mile.
At what speed would it take 45 seconds to travel a mile?

Ans.: 80 mph!

3. Difference between Displacement and Total Distance.

Displacement is just the difference between the coordinate of the final point and the coordinate of the initial point.

For example, a person walks along the number line and begins at the point whose coordinate is zero. That person walks 5 units to the right, then turns around and walks to the left 8 units. What is the displacement and the total distance?

Examine the diagram below. The displacement is -3 because the person wound up 3 units to the left of the starting point. However, the total distance traveled is 13 units (5 units + 8 units).



4. Example



5. Example



6. Additional Examples:



7. Song about Velocity, Acceleration, Distance, and Displacement



8. Assignment
p. 416 (1a,b, 5a,b, 9a, 10a, 13, 32, 34, 40, 41)

Click here to go to the next page




Send any comments or questions to: David Pleacher