High Roller. Objective 1 (E1): To calculate the average speed of the train for one trip.

Transcription

1 High Roller Objective 1 (E1): To calculate the average speed of the train for one trip. SUGGESTED PROCEDURE: Use the given the length of the track and the time required for one trip to calculate the average speed. APPARATUS: Stopwatch DATA: Time required for complete trip: Length of track: 857 m RESULTS: Average speed:

2 Objective 2 (E1): To calculate the speeds at certain points along the track. SUGGESTED PROCEDURE: Determine the length of the train by at least one of the following methods (counting the number of vertical braces covered by the standing train; pacing its length when entering or leaving, etc.), and time its passing at the points indicated below. APPARATUS: Stopwatch Calibrated pace or tape measure DATA: Length of train m Time for train to pass top of tow hill (point A) Time for train to pass bottom of first drop (point B) Time for train to pass top of next hill (point C) Time for train to pass top of "bump" across from Entrance ramp (point D) Time for train to pass bottom of last hill (point E) RESULTS: Speed at top of tow hill (point A) Speed at bottom of first drop (point B) Speed at top of next hill (point C) Speed at top of 'bump" (point D) Speed at bottom of last hill (point E) Objective 3 (E12, E13, E14): To predict speeds at the bottom of the first drop (point B) and the top of the next hill (point C) using energy conservation laws. Compare these calculations with the measured speeds. SUGGESTED PROCEDURE: Calculate the vertical drop of the first down-hill. Using energy conservation, calculate predicted speed at the bottom. Calculate the vertical drop from the top of the tow hill to the top of the next hill and again predict the speed using energy conservation. DATA: Height of tow hill (point A to point B) Height of 2nd hill (point B to point C) m m RESULTS: Predicted speed at bottom of hill (point B) % Difference with measured speed from OBJECTIVE 2 Predicted speed at top of 2nd hill (point C) % Difference with measured speed from OBJECTIVE 2 CONCLUSION:

3 Objective 4 (E7, E18): To compare the acceleration in "g's" at points B, C, and D on the track by measuring with an accelerometer AND by calculation using speed and radius data. SUGGESTED PROCEDURE: Prepare a method ahead of time for calculating the radius of curvature of an arc using chord length and height, and use this to determine the radius of curvature of the bottom of the first hill, the top of the second hill and the top of the "bump" used above. Calculate the centripetal acceleration at each of these locations using the speeds previously calculated. APPARATUS: Vertical accelerometer DATA: Chord length "L" at bottom of first hill (point B): Altitude "h" for this chord: Accelerometer reading: /s 2 Chord length at top of second hill (point C) Altitude for this chord: Accelerometer reading: /s 2 Chord length at top of "bump" (point D): Altitude for this chord: Accelerometer reading: /s 2 RESULTS: Radius at bottom of first hill (point B): Calculated centripetal acceleration in g's: Radius at top of second hill (point C): Calculated centripetal acceleration in g's: Radius of "bump" (point D): Calculated centripetal acceleration in g's: CONCLUSIONS:

4 Objective 5 (E10): To calculate the centripetal acceleration of the train as it goes around the final turn at point E and compare the required super-elevation angle (tilt) with the actual one. SUGGESTED PROCEDURE: Estimate the radius of the final turn by pacing an equivalent distance or by triangulation. Measure the super-elevation angle at the same point at which speed was calculated earlier. Calculate the required angle and compare this with the actual super-elevation angle of the track at that point. DATA: Estimated radius of final turn: Measured superelevation angle of final turn: RESULTS: Centripetal acceleration of train: Required super-elevation angle: degrees /s2 degrees CONCLUSION: Objective 6 (E12, E13, E14): To calculate kinetic energy change during various parts of the ride. SUGGESTED PROCEDURE: Assume the train is loaded with passengers with an average mass of 60 kg. Using speeds from OBJECTIVE 2 calculate the kinetic energies at points A and B. Calculate the kinetic energy change from point A to point B. APPARATUS: Stopwatch DATA: From OBJECTIVE 2: speed at point A, and _ Speed at point B): _ Mass of empty car 730 kg X Number of cars per train = mass of train: kg Number of people per car X mass one person 60_ kg = mass of people on train: kg RESULTS: Mass of train and passengers: kg Predicted Kinetic Energy at point A: J Predicted Kinetic Energy at point B: J Change in Kinetic Energy between points A and B J

5 Objective 7: To collect and analyze pressure data using Sensor Kinetics Pressure Sensor (only Android Smartphones) to produce an pressure profile of the ride. SUGGESTED PROCEDURE: 1. Set Smartphone to stay on at least 5 minutes (this will prevent device from shutting off before all data can be collected). 2. Open the Sensor Kinetics Pro app or similar app. 3. Select the Pressure Sensor. 4. Follow app directions to save and share data as a csv file. 5. Graph results using Excel, Logger Pro or similar graphing app. CONCLUSION: Write a paragraph describing the pressure profile. Objective 8 (E29): To collect and analyze pressure data using Sensor Kinetics Pressure Sensor (only Android Smartphones) to produce an altitude (height) profile of the ride. SUGGESTED PROCEDURE: 1. Set Smartphone to stay on at least 5 minutes (this will prevent device from shutting off before all data can be collected). 2. Open the Sensor Kinetics Pro app or similar app. 3. Select the Pressure Sensor. 4. Follow app directions to save and share data as a csv file. 5. Graph results using Excel, Logger Pro or similar graphing app. 6. Convert pressure data from mbar to meters using conversion factor in Helpful Hints. 7. Graph height (meters) vs time. CONCLUSION: Write a paragraph describing the altitude profile.

6 Objective 9: To gather subjective data about the ride to compare with the direct data and calculations. SUGGESTED PROCEDURE: During the ride concentrate only on how forceful you are "pushed" down into the seat or "lifted" against the retaining bar. If you can, try this with your eyes closed for the duration of the ride! APPARATUS: Clear head, relatively empty stomach, no distractions. DATA: Rate the relative magnitude of the force at the points indicated using the rest position before the ride starts as the neutral (N) reference force. Circle the appropriate letter. Were you pushed Top of first hill Bottom of first hill Top of second hill Middle of first curve Top of last two small hills Middle of last curve INTO THE SEAT or AGAINST THE BAR Large Medium Small Neutral Small Medium Large Objective 10: Compare and contrast a ride on the wooden structure of High Roller with the steel structure of Wild Thing. Give possible explanations for these similarities and differences.. Must have ridden both High Roller and Wild Thing.