Is gravity always 9.8m/s2??
INTRODUCTION: A simple pendulum consists of a mass m swinging back and forth along a circular arc at the end of a string of negligible mass. A pendulum is a weight suspended from a pivot so that it can swing freely. Gravity is the pull that two bodies of mass exert on one another. There are several simple experiments that will allow you to calculate the acceleration due to gravity of a falling object. A simple pendulum can determine this acceleration. The only variables in this experiment are the length of the pendulum (L) and the period of one full swing of the pendulum (T). In this case the independent variable represents the length of the string and the dependent variable represents the period of one oscillation. The control variable is the mass of the pendulum. In this lab our goal was to see if we can prove if the acceleration due to gravity is 9.8m/s2. The R2 in this lab is closed to 9.8 m/s2 . The formula that we used in this lab is T=2πLg and then we solved for g=L(T2π)2. HYPOTHESIS: The gravity will be 9.81 m/s2 at sea level due to the acceleration. PROCEDURE:

Materials: stopwatch, meter stick, support stand, string, mass (200g), rod clamp, protractor. Safety: Be careful not to drop any of the heavy materials or to hit somebody near you by using them. 1. Set up the support stand on a flat surface.

2. Tie to mass at the end of the string in a way that the string would be straight( in this case the mass will be 200g) 3. Measure the distance from the top of the support to the mass attached to the string. ( we used 10 different distances) 4. Pull back the mass keeping the string taut.

5. Measure the angle and keep it relative to vertical ( we kept the angle constant at 20°). We picked a smaller angle so when we would calculate the period we would only get one oscillation per 6. Release the pendulum mass and simultaneously start the stopwatch. 7. Let the pendulum swing through one cycle.

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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...

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Pendulum
Raiyan Hassan
SPH3U
September 20, 2011
Introduction
A pendulum is a device which consists of a mass attached to a string from a frictionless pivot which allows it to swing back and forth. In this experiment, the time it takes for a pendulum to go through a period is going to be measured. The time it takes for a pendulum to go through one period can depend on factors such as the length of the string, mass, or the degree in which the pendulum is released from (amplitude). In this experiment, only different masses will be used in order to prove that mass does not have an effect on the time it takes for a pendulum to go through a period.
Purpose
The purpose of this experiment is to determine the effect of mass on the period of a pendulum.
Hypothesis
If the mass of the pendulum increases then the time for the swing will neither increase nor decrease because the mass does not have an effect on the period of a pendulum.
Materials and Methods
The materials used in this experiment are:
3 Different Masses (20g, 50g, 100g)
Clamp
String
Clock
Protractor
With these materials, the experiment was conducted in the following procedure:
1) Place the clamp to a flat surface with a string attached to it
2) Attach a 20g mass to the end of the string opposite from the pivot
3) Pull the mass to the side with an amplitude of 70º
4)...

...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,...

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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...

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“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
In this lab we had to design a system that would test if changing the mass, angle of release and length would have any effect on the period of a pendulum.
Hypothesis
As the length, mass and angle of release change, the period (T) will change for each one of these factors.
Materials
Lab stand
Protractor
Cardboard
Fishing line
Stopwatch
Weights
Hook for weights
Tape
Ruler
Weighing scale
Logger Pro
Variables
Independent
Angle of release
Dependent
Period
Length of string
Mass of bob
Design
Procedure
First you have to set the lab up as seen above. Draw the protractor on a piece of paper and stick this piece of paper on a cardboard board. Attach this cardboard board to the lab stand with ductape. Attach the string to the lab stand and add the hook with mass to the string.
Then you can start testing the affect of change when the angle of release changes. Look at your protractor and release the pendulum at an angle of 10º. Press the timer as you let go and stop the timer as the bob made a complete cycle. Do this two more times so you have three trials for the release angle of 10º. Then make the angle of release 20º and do three trials again. Change the angel of release with 10º each time for 5 trials.
After testing the affect of change in the angle of release you can start testing the effect of change when you change the...

...LabReport - The Simple Pendulum
Name: XXXXXXX XXXXX XXXXXXX
Date: January 18, 2013
Objective:
Gain insight on how scientists come to understand natural phenomena through theoretical and experimental data by determining the Period of a Simple Pendulum. This experiment will introduce us to the processes of data collection and the procedures used for data /error analysis.
Theory:
A Period of motion is a physical quantity associated with any cyclical natural phenomenon and is defined as one complete cycle of motion. There are many examples of this in nature, such as the earth’s period of rotation around the sun takes approximately 365 days.
The Simple Pendulum is a basic time-keeping apparatus. A weight is suspended on a length of string which in turn is attached to a frictionless pivot so it can swing freely. The time period it takes to complete one swing is determined by the theoretical equation derived from the Physical Theory of Repeating Motions, aka Simple Harmonic Motion.
T=2π〖[L⁄g]〗^(1/2)
Where T is the period, L is the length of the pendulum and g is the acceleration due to gravity,
g=9.81 m/s^2.
Once finding the theoretical period we when can compare it to experimental measured value we found of the period. In gathering the experimental data there will be a degree of uncertainty associated with the gathered values. Because of the uncertainty in gathering...

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PhysicsLabReport#3
“Determining the period of a pendulum”
Name: Fei Huo
Date performed: October 1st, 2014
Period 5
Teacher: Mr. Glasel
Purpose:
The Purpose of this Lab was so that my classmates and I can examine what kind of factors affect the period of a pendulum.
Introduction:
In a simple form, the pendulum is a weight hung from a long string that Galileo discovered that it can be used to track the passage of time very accurately around 400 years ago. In this lab my classmates and I are using the pendulum to determine the value of the accelerations of any object due to gravity.
Procedure:
1) First, you measure the string on the pendulum at 1.0m (meters) long and measure from the pivot point to the center of the mass by using the protractor.
2) Then, displace the bob string to an angle of 20 degrees from its resting position and measure the time required for the bob to complete 20 complete cycles swinging back and forth with the stop watch provide (repeat this process for the pendulum lengths of 0.80m, 0.60m, 0.40m, and 0.20m and keep all other factors constant).
3) Third, record all the data that you got into Table 1.
4) Forth, measure the string at 0.50m and always displace the bob 20 degrees.
5) Fifth, Measure the amount of time to complete 20 swings for the different...