For StudentsEngineering Design in Oregon Science ClassroomsPage 1 of 4
Name ______Period ______
Exploration Activity Handout for Ultimate Speed Challenge
Introduction: In the activity you will be designing and building coaster cars. Doing some preliminary research on how the individual parts of a coaster car affect its travel time and motion will help youdetermine the best configuration of parts.
Article Notes: Write down four key facts about coaster car physics from the Ultimate Speed Challenge article.
1. ______
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2. ______
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3. ______
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4. ______
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Background Paragraph:Turn your article notes into a paragraph about coaster car physics. Your paragraph should include a topic sentence, at least three supporting details, and a concluding sentence.
Predictions:
1. Which sample car will travel the fastest? Why?
2. Which sample car will travel in the straightest line? Why?
Procedure:
1) Following the Building Instructions Handout, build last year’s winning car. This will be yourcontrol.
2) Assign the following roles in your group. Everyone in the group should record data onto their data table.
Releaser: ______
Timekeeper: ______
Swerve Watcher: ______
3) Test the car according using the following procedure.
a)Measure then record the distance the cars will travel down the ramp in Table #1.
b)Measure then record the mass of the control in Table #1.
c)The releaser should place the car on the ramp so that it straddles the center line and the back wheels are at the edge (Figure 1). Check to see if the timekeeperis ready, then release the car dramatically, lifting your fingers so he or she will have a good visual cue to start the timer.
d)The timekeepershould stop the timerwhen the car’s back wheels are off the ramp and on the ground. Record the time on Table #1.
e)The swerve watcher should determine the amount of swerve using the Swerve Guide as a reference. Record the result on Table #1.
f)When all the data is collected,calculate the average time forthe control by addingup the times for each trial and dividing by three.
Extension
g)Take the average time and use it to calculate speed. Record in Table #2.
h)Next, take the speed and use it to calculate acceleration. Record in Table #2.
i)Lastly, using Newton’s 2ndLaw where mass times acceleration equals force, calculate the car’s force.
4) Below are the instructions on how to modify your car. Your teacher will assign your group a modification to build. Circle the instructions that apply to your group then follow them to alter your control car. Use the How to Build Your Coaster Car as a reference.
A) Smaller Wheels: Take off the 20 tooth (larger) wheels on the control and replace them with the 12-tooth (smaller) wheels.
B) Longer Chassis: Exchange the regular sized craft stick chassis for a longer craft stick chassis. Be sure the bearings are still 2 cm from the ends on the larger chassis.
C) More Wheels: Cut another 3 cm bearing from the straw and add it to the middle of the chassis. Slip the axle through the bearing and add 2 morematching wheels.
D) Shorter Wheel Spacing: Change the position of the bearing so instead of being 2 cm from each chassis end, they are 4 cm in from each end.
E) More Mass: Tape a stack of 2 pennies to the middle of the chassis.
5) Follow the procedure from step #3 above to test your modified car.
6) Record your data on the class data sheet.
7)Break down your car into its individual parts and return your materials to their appropriate place.
Data Table #1
Car / Distance(m) / Mass
(g) / Time (sec) / Swerve
T1 / T2 / T3 / Average / T 1 / T2 / T3
Control
Modification
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Data Table #2: Extension
Car / Speed (m/s) / Acceleration (m/s²) / Force (N)Distance ÷ Time / Speed ÷ Time / Mass × Acceleration
Control
Modification
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Analysis Questions:
1. Which car was the fastest down the ramp? Why?
2. Which car travelled in the straightest line? Why?
3. Explain how each of the following modifications affected the car compared to the control.
Smaller Wheels:
Larger Chassis:
More Wheels:
Shorter Wheel Spacing:
More Mass:
4. What is a trade-off you must balance when designing a coaster car?