Projectile problem from the movie Speed - Modeling Physics

Projectile Problem from the Movie Speed
"Speed" is a fun action movie from 1994 starring Keanu Reeves and Sandra Bullock. The
premise of the movie is that a disgruntled former police officer attaches a bomb to the bottom of
a bus. Once the speed of the bus passes 50 miles per hour, the bus must maintain a velocity
greater than 50 mi/hr or the bomb will go off, which would be uncomfortable for the
passengers.
The scene of interest for this assignment involves the bus racing down a new elevated highway
in southern California. Unfortunately for our bus travelers, there is a gap in the highway bridge.
Luckily for our travelers, the laws of physics can be bent (or thrown out entirely) in the movies.
Some details estimated from the movie situation...
Speed of bus:
Length of bus:
Length of bridge gap:
So, if you tried to do the same thing the folks in the movie tried, but in the real world you and I
live in, how would the movie clip look different Present your answer by making a movie or
powerpoint animation that shows the path the bus would actually take.
[] Project elements:
• Clear and organized calculations. State what you were calculating and show how you did it. (A
data table would be nice with columns for time, real x position, real y position, scaled x
position, and scaled y position.)
• Make an animation of at least ten pictures. At least five pictures should show the bus in the
gap in the highway.
• Write a one page explanation of the process used in order to make the animation.
• Grading rubric
Hints on how to get started:
• Convert the lengths and speeds to metric units. 1609 meters = 1 mile; 3.3 ft = 1 meter
• Calculate how long it would take the bus to cross the gap.
• Choose a timestep between pictures that is small enough so that you have at least 5 pictures of
the bus in the gap.
• Calculate the x- and y- positions at each time, then convert them to the scale of your diagram.
(1 meter = 1 cm, for example)
[] The assignment is worth 50 points.

Speed Project Animation – Nearly Step-by-Step Directions
You can figure out the rest – be a persistent problem solver!
The steps below outline a basic technique that will lead to successful completion of the project.
However, there are much more sophisticated ways of completing this project, and I encourage
you to pursue them as your time and interest allow.
Preparing the Data
-complete conversions, determine timestep, and calculate x- and y- positions at each time
-find the scaling factor:
-find length of screen in cm
-find a scene length in meters that will give you enough room for your animation
-divide width of screen (cm) by length of scene (m) to get the scaling factor (cm/m)
(you will have to begin the animation process below to determine the screen width)
-multiply the X and Y positions (in meters) by the scaling factor (cm/m) to find the location of
the bottom of the front tire of your bus in each frame
Making the animation – Powerpoint, Appleworks Presentation, or Keynote
The directions vary slightly for each program, so search until you find equivalent commands
-under the “view” menu, check “rulers” (under the “format” menu, choose “rulers”)
-under the “Powerpoint” menu, select “Preferences,” make the ruler units “centimeters”
-convert length of your gap to centimeters to fit the computer screen
-with a drawing tool, mark edges of the gap according to your calculations
-draw the bridge on both sides of the gap all the way to the screen edges, add details and color
-use the selection tool to make a box around all bridge elements under the “Arrange” menu,
choose “Group”
-draw the bus to scale (see the bus photos or the scale model) and color the bus.
-use the “Group” command: the bus can now be moved around as one object
-move the bus to the starting position,
-from the “edit” menu, “select all” (or use “command” + “a”)
-from the “edit” menu, “copy” (or use “command” + “c”)
-create (or insert) a new slide
-in the new slide, from the edit menu, “paste” (or use “command” + “v”)
-move the bus according to your calculations
-repeat process frame by frame until you have completed at least ten frames with at least five of
those frames in the gap
-add background or other details
-click “view presentation” or “play slideshow”
-set playback to automatically advance one frame every second
In the past students have also used AutoCad3D, Google SketchUp, Adobe Flash, Windows
Movie Maker, iMovie, and stop-motion animation (see http://www.samanimation.com/). Enjoy
the project – I often comment on the problem solving abilities I see in this project when writing
college recommendations.