Experiment on Measurement
Motion
Zia C. Martin

Department of Math and Physics
Angeles University Foundation, Angeles City zia12_martin@yahoo.com Abstract This paper aims to help identify the similarities and differences between walking, jogging and running motion. The motion of an object is the change in its position with reference to a fixed point. Increasing the speed means positive acceleration while decreasing speed means negative acceleration. When a moving body increases its speed with the same amount over a certain time interval, it has constant acceleration.

I. Introduction:
In this experiment, we’ll be able to determine the similarities and differences of walking,jogging and running.

Motion is a change in position of an object with respect to time. Motion is typically described in terms of velocity, acceleration, displacement, and time. Motion is observed by attaching a frame of reference to a body and measuring its change in position relative to another reference frame.

A body which does not move is said to be at rest, motionless, immobile, stationary, or to have constant position. An object's motion cannot change unless it is acted upon by a force, as described by Newton's first law. An object's momentum is directly related to the object's mass and velocity, and the total momentum of all objects in a closed system does not change with time, as described by the law of conservation of momentum.

II. Theory In this activity, we learned to identify the similarities and differences between walking, jogging and running motion. The speed of an object does not give its direction. If speed is accompanied with direction, it is called velocity. Uniform motion is a type of transitional motion in which the speed of a moving object does not change within a time interval. The motion of the object is not accelerated therefore its acceleration is zero.

III. Methodology The materials needed for this experiment are meter stick and stop watch.

1. Measure 3.5m on the floor, mark the starting point x and the end point y.
2. Let one member of the group walk from x to y.
3. Repeat step 2, but this time, let another group member jog jog from point x to y.
4. Finally, let another member run from point x to y.
5. Make three trials for step 2,3 and 4. Figure 2.walking, jogging and running

IV. Results and Discussion
The results obtained in our experiment are the following:

Mass and Acceleration Data
Trial t (sec) walking t (sec) jogging t (sec) running Distance (m)
1 3 s 2.6 s 1.12 s 3.5 m
2 2.97 s 1.85 s 1.28 s 3.5 m
3 2.56 s 1.85 s 1.13 s 3.5 m

Figure 3.Graph for walking, jogging and running

The data above is the result of the trials we made when me make our members walk, jog and run. Using a fixed distance we can see the differences between walking, jogging and running by looking at the time it took for the members to walk, jog and run from starting to end point.

V. Conclusion After performing such experiment we understand and realize the similarities and differences of walking, jogging and running. In each trial there’s just a small discrepancy on time.

References
[1]http://en.wikipedia.org/wiki/Motion_(physics)
[2] Flores, E. Physics 1 Laboratory Manual and Workbook. C & E Publishing Inc., 2009

Experiment on Measurement
Freely-Falling Body
Zia C. Martin

Department of Math and Physics
Angeles University Foundation, Angeles City zia12_martin@yahoo.com Abstract This paper aims to help measure the acceleration of an object due to gravity. It also aim to compare the experimental or the computed value of g to that of the theoretical or true value. The acceleration of an object in free fall is uniform and it is called “acceleration due to gravity” which is represented by the symbol g.

VI. Introduction:
In physics experiments, experimental/computed value is use to determine the amount of error a data has with its true value.

Free fall is any motion of a body where its weight is the only force acting upon it. These conditions produce an inertial trajectory so long as gravity remains the only force. Since this definition does not specify velocity, it also applies to objects initially moving upward. Since free fall in the absence of forces other than gravity produces weightlessness or "zero-g," sometimes any condition of weightlessness due to inertial motion is referred to as free-fall. This may also apply to weightlessness produced because the body is far from a gravitating body.

VII. Theory In this activity, we learned to determine the relationship between acceleration and mass of a body acted upon by a constant force and the force and acceleration of a moving body provided its mass constant.When an object is dropped, its velocity starts at zero and it accelerates positively. It is a remarkable fact that in vacuum all falling object have the same acceleration. This rule does not hold in everyday experience only because the resistance of air tend to hold things back. A freely body is one which gravity is the only force acting on it. All forces, such as air, resistance and the weight of the object, are assumed to be zero or at least negligible.

Formulas: Note:where is the height of the fall, is the time to travel the said height and is the experimental value of acceleration due to gravity.

Note: Time taken for an object to fall distance

Note:The symbols in the above equation have a specific meaning: the symbol d stands for the displacement; the symbol tstands for the time; the symbol a stands for the acceleration of the object or the constant gravity of an object which is 9.8 m/s2; the symbol vi stands for the initial velocity value; and the symbol vf stands for the final velocity.

VIII. Methodology

The materials needed for this experiment are meter stick, stop watch and metal ball.
1. Assign fixed heights as the vertical distance from the base to the ground.
2. For three trials per assigned fixed height, record the time it takes for the metal sphere to travel the assigned vertical distance.
3. Record your data.
4. Compute for the experimental value of gconsidering the three assigned heights.
5. Compute for the percent error to verify the success of your experiment.

Figure 1.Free fall

IX. Results and Discussion
The results obtained in our experiment are the following:

Distance:1.5 meters

Trial Time g
1 .47 s 13.58
2 .41 s 17.85
3 .45 s 14.81

Averageg(Experimental) : 15.41 m/s2
Value of g (True Value) : 9.8m/s2
Amount of error : 5.61
Percent error : 57.24%
Distance:2 meters

Trial Time g
1 .52 s 14.79
2 .54 s 13.72
3 .55 s 13.22

Averageg(Experimental) : 13.91 m/s2
Value of g (True Value) : 9.8m/s2
Amount of error : 4.11
Percent error : 41.94%

Distance:2.5 meters

Trial Time g
1 .62 s 10.81
2 .64 s 12.20
3 .52 s 18.50

Averageg(Experimental) : 13.84 m/s2
Value of g (True Value) : 9.8m/s2
Amount of error : 4.04
Percent error : 41.22%

The data above is the result of the trials we made using different heights 1.5m, 2m and 2.5m. As a result you can see that the percent of error is huge. The results also shows that as the value of distance increases the value of time also increases but the value of gdecreases.

X. Conclusion After performing such experiment we understand and realize the comparison between the experimental/computed value to that of the theoretical/true value of g. However, you can see that the percent error in this experiment is huge. These conclude that in this experiment there is a 50:50 chance of getting an accurate measure.

References
[1] http://en.wikipedia.org/wiki/Equations_for_a_falling_body
[2] http://www.physicsclassroom.com/class/1dkin/u1l6c.cfm
[3] http://en.wikipedia.org/wiki/Free_fall
[4] Flores, E. Physics 1 Laboratory Manual and Workbook. C & E Publishing Inc., 2009