Experiment 4: Composition and Resolution of Concurrent Forces

Summary:

In this experiment, we determined various scalar equilibrants and resultants using three methods: experimental (trial and error balancing of a pulley system using different weights and angles), mathematical, and parallelogram methods. An equilibrant is a vector that counterbalances the forces acting on a body, has an equal magnitude to the resultant, and acts in an opposite direction to the resultant. The experimental method did not involve equations, angles and weights were measured directly. The parallelogram method involved measuring angles directly with a protractor, and also did not require trigonometric functions. The mathematical method employed resolving vectors into their x and y components. The components of FA were determined using equations: The Resultant vectors were determined using equation: (Rx and Ry were determined by adding the x and y components of the vectors)

The angle made with the x axis by the resultant vector was determined using the equation:

Conclusion:

The experimental method appeared to be most accurate method of determining the resultant and its angle. The mathematical method should have been the most accurate because there was no opportunity for human error in measurement recording. Our group results were different than expected because of human error; a miscalculation of the angle of the resultant in the experimental method caused it to be higher than normal.