Title: Atwood's Device
Author: Saige Miller
Partner: Kelly Schneck
Date: 11-12-15
Author: Saige Miller
Partner: Kelly Schneck
Date: 11-12-15
Purpose
The purpose of this lab is to investigate Newton's Second Law, the idea of constant acceleration between two objects of unequal masses, using Atwood's Device.
Theory
George Atwood lived from 1746 until 1807. He is most commonly known for his creation of Atwood's machine, consisting of a mass-less, non-stretch string connected to friction-less pulleys. On either side of the pulley are masses M and m (unequal masses). The device challenges Newton's Second Law, and proves constant acceleration despite varying masses. Students and physicists today still use similar machines when investigating Newton's second law.
|
Experimental Technique
A string connected to hangers on either side was draped over a Smart pulley and Photo-gate system. Weight was added to both hangers, one heavier than the other. Next, the heavier weight was elevated so that the lighter weight was in position resting on the table. The weight was then released and the acceleration was measured by the Photo-gates. This was done three times, each weight differed by 10 grams.
|
Data
Analysis
Conclusion
The purpose of the lab was to investigate constant acceleration between two different masses. Each trail, the calculated mass was slightly higher than the measured acceleration. As the total weight increased, the percent difference decreased, conveying the predicted acceleration to be closer to the measured acceleration.
The weight used for each trial had a big influence on the acceleration. The lighter the total weight, the greater the acceleration. As more weight accumulated between the hangers, the acceleration decreased. The difference between the predicted acceleration and the measured acceleration could be a result of the inaccuracy of the graphs used to calculate acceleration. To reduce error, I lowered the hanger with the smaller mass to table where it would naturally land, so that it was straight down from the pulley. Also, I put my finger on the string on the pulley and let it go from there to reduce swaying of the string.
The weight used for each trial had a big influence on the acceleration. The lighter the total weight, the greater the acceleration. As more weight accumulated between the hangers, the acceleration decreased. The difference between the predicted acceleration and the measured acceleration could be a result of the inaccuracy of the graphs used to calculate acceleration. To reduce error, I lowered the hanger with the smaller mass to table where it would naturally land, so that it was straight down from the pulley. Also, I put my finger on the string on the pulley and let it go from there to reduce swaying of the string.
References
http://physics.kenyon.edu/EarlyApparatus/Mechanics/Atwoods_Machine/Atwoods_Machine.html
Giancoli, D. (1998). Physics: Principles with Applications (5th ed.). Upper Saddle River, N.J.: Prentice Hall.
Atwood Machine. (2015, July 9). Retrieved November 12, 2015, from https://en.wikipedia.org/wiki/Atwood_machine
Giancoli, D. (1998). Physics: Principles with Applications (5th ed.). Upper Saddle River, N.J.: Prentice Hall.
Atwood Machine. (2015, July 9). Retrieved November 12, 2015, from https://en.wikipedia.org/wiki/Atwood_machine