Atwood Machine Experiment

Atwood Machine Experiment

ABSTRACT

In measuring the acceleration of an object, it is observed that this acceleration will be directly proportional to the net force acting on the body and also inversely proportional to the total mass of the object.

INTRODUCTION

In this lab, we are finding the acceleration using the test of Newton’s 2^nd law while utilizing an Atwood machine as the apparatus. From the Atwood machine, we primarily get the relationship which exists between thee mass, net forces and also the acceleration. From the net force, there is the distribution of the masses with the weights which is an independent variable that is a constant and the time being the dependent variable which increases within the experiment.

PROCEDURE

We wanted to measure the acceleration of an object using an Atwood machine. The apparatus consisted of an Atwood with one pulley with a string attached over the pulley to two weight hangers that is a set of weights. From the first method the total masses were kept the same but there was a mass difference. The masses from this first method were moved from one side to the other and the experiment was repeated five times. The second method involved the total mass and from this the was an increase in the total mass and the same mass was being added to each weight hanger. This method was repeated four times and the data was recorded. From the compute connected to capstone, a value of acceleration can be gotten when the setup is put in place.

Fig 1. Free body diagrams of the experimental setup

THEORY

In the Atwood’s machine experiment, two masses are suspended from a string on either side of a pulley. The larger mass, m_2, provides a net force and its equation is below.

It is also possible to get the acceleration from the capstone program. Acceleration can be determined by then from the graph on the capstone program and then compared to the value. calculated from the given masses. Differences may occur due to errors that may have occurred during the experiment.

RESULTS

From the first method of the experiment, when there was a mass difference, it was shown that increasing the mass difference between the two weights made the time of fall shorter while in the second method, as the mass was increased on the both sides with the same difference, the time taken for the heavier weight to reach the ground was longer and the acceleration was increasing.

Equations

g

TABLES AND CHARTS

1. Increasing mass difference (Total mass = 100g)

m_1 (g)	m_2 (g)	Acceleration from capstone (m/	Acceleration from calculation (m/
10	90	6.99	7.84
20	80	4.69	5.88
30	70	8.05	3.92
40	60	1.71	1.96

2. Increasing mass sum

m_1  (g)	m_2 (g)	Acceleration from capstone (m/	Acceleration from calculation (m/
40	60	1.73	1.96
60	80	1.31	1.4
80	100	0.98	1.1
100	120	0.83	0.8

CONCLUSION

From the Atwood’s machine, we see that Newton’s 2^nd law was successfully demonstrated. From this experiment, the acceleration was determined from the masses being added and the value of acceleration being calculated from the equation of the two combined net forces. The results show. that the acceleration of an object. is directly proportional to. the net force acting on the object and inversely proportional to the total mass. of the object. Sources of errors in the data include the frictional force in the Atwood machine and the observer’s reaction time.