Purpose
The reason for this experiment is to prove that objects of different masses, when dropped from the same height, fall at the same velocity.

Apparatus
- 2 Marbles of different mass, one steel and one nylon
- Dropping Mechanism with a lever to hold the marble and pull for drop - Bee Spi (measures velocity in kilometers per hour.)
- Box to catch the marble on the way down

Procedure
The dropping mechanism was set up, with the BeeSpi attached to it at 26.5” from the lever that drops it so that the marble would fall through it, therefore recording the velocity in km/h. There was also a box at the bottom of the mechanism to catch the marble every time it was dropped. Both the steel and the nylon marble were placed in the lever at the top of the dropping mechanism and dropped 5 times each, and the velocity was recorded for each time.

Data
Velocity in km/h
Steel Marble Nylon Marble
￼

Evaluation of Data
Each marbles’ velocity was averaged. The steel marble’s average came to 13.203 km/h, while the nylon marble’s came to 12.974 km/h. In order to get the units in more familiar terms, a TI-84 graphing calculator was used to convert the units from km/h to m/s. After doing that, the steel marble’s average velocity was 3.67 m/s, while the nylon marble’s was 3.603 m/s.

Also, by using Google Earth, the average gravity of the room in which the experiment occurred was found to be -9.79788 m/s2 , while the MSL(mear sea level), otherwise known as elevation, was found to be 823 ft.

Conclusion
The results of this experiment were very close to being accurate. The difference of the average velocities was only 0.067m/s. There are many reasons that that difference occurs. First of all, the experiment wasn’t taken place in an airtight vacuum, therefore air resistance played a part in it. If the air conditioner was on for one part of the test, and off for another, the data would be completely different. Also, the friction between the lever and marble...

...WRITING RESEARCH REPORTS
The following set of guidelines provides psychology students at Essex with the basic information
for structuring and formatting reports of research in psychology. During your time here this will be
an invaluable reference. You are encouraged to refer to this document each time you write a labreport.
The writing of laboratory reports is an essential part of any practical module in Psychology. This is
because psychologists (and more generally most scientists) write accounts of their studies using a
standard format, which makes explicit certain aspects of the study. There are two main reasons for
doing this:
(1) Ease of communication: it is easier to find what you want from a study if it
is written in the standard format.
(2) Provision of a precise and complete description: the format makes it clear what
information is important for scientific communication. This information must be provided
in detail. It should be added that many professions now include the skills of technical report
writing, which requires clear, direct and concise
expression, the ability to summarize and present data, and the ability to form
hypotheses and draw valid inferences. Learning to write laboratory reports will provide you
with a valuable and transferable skill.
This guide tells you about the structure and style that is required for a psychology laboratory...

...
PhysicsLabReport
How does the length of a string holding a pendulum affect its oscillation?
Method
1. You will need the following apparatus: a pendulum, a piece of string, a clamp, a clamp stand and a timer.
2. Measure out 20cm and attach the metal ball.
3. Establish an angle and let the ball swing for 10 oscillations, timing it and stopping at the 10th one.
4. Write down your results.
5. Repeat steps 2-4 another 2 times so that your results are reliable.
6. Then change the length of the string 4 times, so that you get 5 different sets of results and for each time, repeat it 3 times.
DCP
Raw Data
Data Processing
Calculations:
To find the average of the time, I added all 3 values and then divided by three. For example:
(0.89+0.83+0.89)/3 = 0.87
I calculated the absolute uncertainty by considering the furthest point from the mean. For example:
1.31 (mean) – 1.25 (furthest point from the mean) = 0.06
Therefore my absolute uncertainty is +/- 0.06
I calculated the percentage uncertainty by dividing the absolute uncertainty by the mean and multiplying it by 100, like this:
(0.03/1.70) x100 = 0.18%
Source of uncertainties:
The uncertainties in the measurement came primarily from the equipment. Since we used a ruler that was divided into parts of 0.1cm, the readings were normally rounded up or down. The length of string was constant in all 3...

...trials were performed or if the class data were to be compared and averaged. Performing the experiments under a vacuum and frictionless setting would remove external variables that affect the data leading to more precise numbers. More accurate percent discrepancies illustrating laws of conservation can be achieved by adding more trials and including more sophisticated measuring tools. These techniques would lead to more accurate results to reduce any experimental errors and to better validate the concepts of energy and momentum conservation.
Conclusion
The purpose of the experiment was to investigate simple elastic and inelastic collisions to study the conservation of momentum and energy concepts. The objective of the lab was met since the validity of the Law of Conservation of Momentum was confirmed by determining the relationship of energy and momentum conservation between inelastic and elastic collisions by utilizing percent discrepancy calculations. The calculations state that the percent discrepancies for inelastic collisions were 8.75% and 19.23 % for the equal mass and unequal mass respectively. The percent discrepancies for the equal and unequal mass elastic collisions were 22.07% and 9.78 % respectively. Both of the percent discrepancies for the elastic collisions were close to the 10%-15% range which validates the concept of momentum conservation in inelastic elastic collisions. In regards to conservation of energy,...

...
Experiment 7: Relative Density
Laboratory Report
Marella Dela Cruz, Janrho Dellosa, Arran Enriquez,
Alyssa Estrella, Zacharie Fuentes
Department of Math and Physics
College of Science, University of Santo Tomas
España, Manila Philippines
Abstract
The experiment was conducted to show the different methods on how to determine an object’s composition through its density and to determine an object’s density by displacement method and the Archimedes Principle. Results show that. The materials used were the spring scale, beaker, 25 pieces of new 25 centavo coins, a bone from a pig’s leg, diet and regular soft drinks, and a pycnometer.
1. Introduction
Density is a physical property of matter. It is the mass per unit volume of a substance. In this experiment, relative density is also used to be able to determine the composition of the substances or objects used. Relative density is the ratio of a density of a substance to that of the density of a given reference material. It is also known as specific gravity. Density is used when making or building objects that are required to float such as ships on water and airplanes in the sky.
Objectives:
1. To determine the density of an object by displacement method
2. To determine the composition of a substance based on its density
3. To determine the density of a substance by Archimedes Principle
2. Theory
Relative Density (R.D.) or also known as Specific gravity (S.G.), is the raito of...

...
“The Domino Effect”
Teacher’s Prompt
Investigate the domino effect with a set of dominoes.
Aim
To investigate the relationship between the mass of the dominoes, and how it impacts the time taken of the domino effect.
Independent Variable: The mass of each domino (12.38 g, 32.38 g, 42.38 g, 62.38 g, 82.38 g).
Dependent Variable: Time taken of the domino effect.
Controlled Variable: The number of dominoes used (8 dominoes), the distance between the dominoes (2 cm), the loads used as the initial force applied on the domino (50g), the inclined plane used as a platform that will direct the load to hit the first domino (20o), the stopwatch used to time the domino effect, the person using the stopwatch, the person releasing the metal weight from the top of the inclined plane, the ruler used to measure the distance between the dominoes.
Equipment
1 Inclined Plane
1 (50 g) Metal Weight
4 x 8 (20 g) Metal Weight
8 Dominoes (Uno Stackos)
1 Digital Mass Balance (± 0.01 g)
1 Masking Tape
1 Protractor
1 Ruler
1 Stopwatch (± 0.01 s)
-34290039687500Diagram
Analysis of Variables
Independent Variable:
The mass of the dominoes will vary ranging from 12.38 g to 82.38 g. The increase between each of the variable will be constantly 20 g, to satisfy the range of the mass; the original mass of the domino is 12.38 g, and an additional mass from a 20 g of load will be attached on top of the domino for every change in variable.
Dependent Variable:
In accordance to...

...Introduction.
Friction was studied in this lab. The experiments were conducted using a clipboard glued to various surfaces with diffirentiating frictional properties. In order for us to test the varying Static friction or Kinetic friction we used a Newton force gauge, some wooden blocks, and a metal weight. The actual experiment consisted of two parts. The first part measured the net force, or more specific the net force required to overcome the kinetic friction coefficient, to move the block across the frictional surfaces (the Clipboard itself, cork, rubber, and sandpaper). The second used inclined angles and the length of the clipboard to measure the static friction coefficient using the equation Tan(N0)= MuStatic.
Theoretical analysis.
In this labreport we measured the kinetic and static coefficients of friction. The hypothesis suggested that the net force requirment of a moving object at a constant speed across a frictional surface is less than the initial force required to start the object into motion due to the frictional coefficients respectivly. The following are the tables of data compiled from the experiments.
Data Collection, Analysis and Results.
Net Force required to move the following objects across the frictional surfaces:
Data Collected: Clipboard: Cork: Rubber: Sandpaper:
1 Block .1N .2N .2N .3N
2 Blocks .2N .4N .5N .6N
2 Blocks & Weight .3N .6N .7N 1.0N
Kinetic friction...

...Kathryn Marchessault
PhysicsLab LR
Tuesday 8-9:55
Due 02/26/15
Experiment #1
Free Fall Experiment
Abstract
In this experiment we studied the motion of an object in free fall, that is an object being dropped from a certain height to Earth’s surface. In this experiment we tested the idea that no matter what the size, shape, color, etc. of the object if it would still experience the same constant acceleration throughout its fall (short distance). The constant downward acceleration it experiences is due to Earth’s gravitational force (g). We measure the position, and velocity of a ball to get the experimental g. We then measured reaction time with a ruler. We used our data and g, to get an average distance and time.
Report Questions
1. The parabolic curve opens upward in the position vs. time graph, because this graph is measuring the position of the ball from the sensor. The ball is at first falling down and then bounces back up. This would cause the ball to move away from its original position, downward, and then as it hits the floor and bounces back up the graph would show this by curving back up to its original position.
2.
The slope of the velocity vs. time graph represents the acceleration of the object. If you were to take the derivative of this graph, you would get the graph for acceleration vs. time. Since the object shows the velocity graph as a straight increasing line, this shows that the slope is constant,...

...
Centro de investigación y desarrollo de educación bilingüe (CIDEB)
PhysicsLABREPORT
Uniform Rectilinear Motion
Teacher: Patrick Morris
Alejandra Castillejos Longoria
Group: 205
ID: 1663878
Abstract
The purpose of this experiment, was to prove the concept of the uniform linear motion by using an air track. With this, we demonstrated the impulse and change in momentum, the conservation of energy and the linear motion. We basically learnt to calculate the distance/time, acceleration/time, and velocity/time and graph it. The air track is also used to study collisions, both elastic and inelastic. Since there is very little energy lost through friction it is easy to demonstrate how momentum is conserved before and after a collision. According to the result, the velocity of the object in the air track was constant, it means that it didn’t have acceleration because it has constant velocity.
Introduction
First of all; we should understand what is linear motion. Linear motion is motion along a straight line, and can therefore be described mathematically using only one spatial dimension. Uniform linear motion with constant velocity or zero acceleration. The Air Track can be used to obtain an accurate investigation of the laws of motion. A car or glider travels on a cushion of air provided which reduces friction. Since the friction is all but removed the car...