Enrichment - Pendulum Project

Look up and write a paragraph or bullet points about the question below (use notebook paper).  You must include 6 sentences or bullet points.


-What is a pendulum
-When pendulums were created?
-What does a pendulum look like?
-Who used pendulums and who discovered them?
-What is it measuring?
-Any other important information

Use the websites below or others to help you find the information:

http://en.wikipedia.org/wiki/Pendulum

 http://goo.gl/hBMKOV

STOP

Name________________________________________________

Phase 1: Learning Objectives and Introduction

Students will design and conduct an experiment to determine how the length of a string and how the weight affect the number of swings of the pendulum.

A pendulum is an object, hung from a fixed point that swings freely back and forth under the action of gravity. A playground swing is an example of a pendulum. The swing is supported by chains that are attached to fixed points at the top of the swing set. When the swing is raised and released, it will move freely back and forth. The swing is moving due to the force of gravity on the swing. The swing continues moving back and forth until friction (between the air and the swing, and between the chains and the attachment points) slows it down and eventually stops it.

We see pendulums in other areas of our lives as well, such as in long-case clocks, commonly known as grandfather clocks. But pendulums can do more than entertain and help us tell time. Among other applications, they can show that the Earth is rotating! This was done in the mid-1800s C.E. using perhaps the most famous pendulum, Foucault's pendulum. However, pendulums were being used for centuries before this. One of the first known pendulum uses was around 100 C.E., when a Chinese scientist, Zhang Heng, used it to detect distant earthquakes in a device called a seismometer. Today, pendulums have many applications, including measuring local gravity and helping guide ships and aircrafts. 

You will investigate how the period of a pendulum is affected by different variables.  A pendulum's period is the time it takes the pendulum to swing back to its original position. In the example of a kid being pushed in the swings at a playground, this is the time it takes the kid to be pushed and then return back for another push. 

Phase 2: Understanding the Experiment

Materials: String, masking tape, timers, washers

Three Variables being tested: length, weight, and angle

Pick your Hypothesis: If I change the length to be (longer/shorter), the weight to be (bigger/smaller), and the angle to be (higher/not as high), then my pendulum will have (more/less) periods per minute.

Initial Setting Up the Pendulum Experiment: To do this experiment requires a little building work

1.     The pencil should be firmly taped to the top of the tabled, leaving about 4cm hanging over the edge.

2.     Next make a loop in your 20 inch string to fit on the end of the pencil but do not make it too tight fitting.

3.     At the other end of your string tie your washers (you will change the weight so not too tight of a knot)

4.     Before performing the pendulum experiment, make sure that everything swings freely without sticking.

Phase 3: Investigate 

Pick your Variables:  I have chosen Trial 1 for every team and you must choose how to adjust the    variables for Trial 2 and Trial 3.

                 

	Trial 1	Trial 2	Trial 3
Amount of Washers	5 Washers
Length of String	20 Inches
String Angle	45 Degrees

Record your Data: You will swing your pendulum for 30 seconds and count the number of periods (full swings) for that trial. When you have that number, multiple it by two and place it in the chart below

	Trial 1 – Period Number (x 2)	Trial 2 – Period Number (x 2)	Trial 3 – Period Number (x 2)	Average Period per minute
5   Washers
_____ Washers
_____ Washers

	Trial 1 – Period Number (x 2)	Trial 2 – Period Number (x 2)	Trial 3 – Period Number (x 2)	Average Period per minute
20       Inch String
_____ Inch String
_____ Inch String

	Trial 1 – Period Number (x 2)	Trial 2 – Period Number (x 2)	Trial 3 – Period Number (x 2)	Average Period per minute
45       String Angle
_____ String Angle
_____ String Angle

Graphing your data: Use your Average period per minute for each different variable and create THREE different graphs.  You may make it by hand on the section below or you can use excel if you understand how to use it. Make sure that they have a Title and the x/y axis is labeled. 

Phase 4: Conclusion

You will prepare a lab report individually. It may be typed or written, but turned into the teacher by the end of the class period on Monday.  Be sure that each member of the group has a copy of the data, reports will share data, but conclusions and writing are individual. Your report should include:

1. Introduction: (Includes background knowledge, hypothesis, and purpose)

2. Procedure (explains how you will test it, pictures can be used)

3. Data table (any data table that is relevant to understand your hypothesis)

4. Conclusions - Make sure you use your data to answer the question. Remember you have three variables in the experiment – length, angle, and weight. Both may have differing affects on the number of swings. Its up to you to find out exactly how each variable changes the pendulum's period (swings per minute)

5. Use the grading rubric to check that you have all parts of the lab report included. 

Phase 5: Debrief and Reflection on Work

Grading Rubric
	Needs Work (2)	Satisfactory (3)	Excellent (4)
Introduction & Hypothesis	Experiment objective is not clear, hypothesis would be difficult to test; reader does not get a clear sense of what will happen in the experiment	Hypothesis is a testable statement, with a clear goal. Variables are included, or a statement that explains what tests will be conducted.	Clearly written and can be tested in an experiment. Variables clearly stated and are separated with respect to the prediction.
Procedure	Procedure is lacking details, could not easily be repeated, missing sketches	Explanation of procedure is included; unclear at parts or missing sketch	Clear explanation shows how data was collected, including a sketch of the lab set-up.
Data Tables	Data is minimal, disorganized, trends not evident, looks like a rough draft	Data is included, but parts may be difficult to read. Trends are not obvious. Some labels may be unclear.	Organized, each column or row is labeled; any reader can clearly see the trends in the data. Graphs
Conclusions	Concluding statements unclear or off topic. Data is not used to support statement or conclusions do not follow data.	Data is used to state an outcome of the experiment, supporting statements (data) unclear or missing elements, conclusion only partly follows data	The data is used to clearly state the outcome of the experiment; the hypothesis is either supported or rejected, conclusion follows data.
Data Gathering-- experiment	Student did not remain on task, did not clean up or return equipment, very little data was collected.	Student was on task most of the time, some data was collected, work space was cleaned and equipment was returned	Enough data was collected to draw conclusions, student remained on task, work space was cleaned and equipment was returned  (information and lab gathered from several different online sources)