A common way of analyzing the motion of objects is to perform a ticker tape analysis. A long tape is attached to a moving object and threaded through a device that places a tick upon the tape at regular intervals of time - say every 0.2 second. As the object moves, it drags the tape through the "ticker," thus leaving a trail of dots. The trail of dots provides a history of the object's motion and therefore a representation of the object's motion. The distance between dots on a ticker tape represents the object's position change during that time interval. A large distance between dots indicates that the object was moving fast during that time interval. A small distance between dots means the object was moving slow during that time interval. The analysis of a ticker tape diagram will also reveal if the object is moving with a constant velocity or accelerating. A changing distance between dots indicates a changing velocity and thus an acceleration. A constant distance between dots represents a constant velocity and therefore no acceleration. And so ticker tape diagrams provide one more means of representing various features of the motion of objects.
ERROR ANALYSIS
1. Equipment Error: During the experiment there were difficulties that sometimes occurred with the ticker tape timer. Though the machine worked quite effectively the problem was encountered with the black carbon disc that created imprints on the ticker tape paper. During the experiment on two occasions the disc would either not imprint anything on to the ticker tape paper or come off during that experiment. This resulted in trails having to be repeated and the waste of l ab materials to retrieve accurate data. 2. Inherent Error: There’s always potential for inherent errors during an experiment and this one is not an exception. The cart being released and the operation of the ticker tape timer were done by two different group members. This created the possibility for the cart to be released slightly before or after the ticker tape timer was activated. Though it may not seem drastic because the time measurements being recorded are so miniscule such a synchronization problem can significantly change in average velocities per interval.
3. Improvements: There are two major improvements that can be proposed to make the data collected from this experiment more precise and accurate. The first improvement would be the creation of a tool to allow one person to operate both the ticker tape timer and release of the car. By creating a release button that would operate both devices it would synchronize them and ensure the data was precise. Also placing groove on the board which the car could run along on the ramp would allow the car to have a constant start and end track on the board. This would eliminate the variation of places the car could start and finish from and the chance of the car falling of the board near the end of its run.
QUESTION
How do you expect to see on the ticker tapes and tape charts if the motion of the body show: I.
Constant speed ? Ticker tape will give reading a constant distance between dots, represents a constant velocity and therefore no acceleration. Tape chart will have same tape length with increasing time.
II.
Increasing speed (acceleration) ? Ticker tape will give reading an increasing distance between dots, represents an increase velocity and acceleration. Tape chart will show increasing tape length with increasing time.
III.
Decreasing speed (deceleration) ? Ticker tape will give reading a decrease distance between dots, represents a decrease velocity and acceleration. Tape chart will show decrease tape length with increasing time.
CONCLUSION
In conclusion, we are able to analyze linear motion of a moving object. From the graph tape chart, we are also able to determine displacement, velocity and acceleration the linear motion. Through the calculation we can observe whether the motion is in constant speed, increasing (acceleration) or decrease (deceleration). To determine the displacement of the cart, find the length of ticker tape and to find the acceleration of the cart, find the final and initial velocity per time. The data collected from this experiment was quite accurate and testing was performed quite smoothly, however as stated early, there is always room for improvement.
REFERENCES
1) http://www.physicsclassroom.com/class/1dkin/u1l2b.cfm 2) http://schoolworkhelper.net/ticker-tape-lab-answers/ 3) http://spm-physics-402.blogspot.com/2009/01/finding-acceleration-from-tickertape.html 4) W. Bolton, Engineering Science, 5th Edition, Elsevier Newnes, Linacre House, Jordan Hill, Oxford OX2 8DP 30 Corporate Drive, Suite 400, Burlington, MA 01 803, 2006.
