It is a short and easy lab, but I would like you to help answer all the \"Click
ID: 2303605 • Letter: I
Question
It is a short and easy lab, but I would like you to help answer all the "Click or tap here to enter text." questions+ the table and the An Excel spreadsheet only.
Data collection:
How long a string would you like to use for the pendulum? Select one of the choices below by clicking on the text.
56.0-cm long string
Trial 1 = 0.0162s
Trial 2 = 0.0192s
Trial 3= 0.0118s
Trial 4= 0.0089s
Trial 5= 0.0562s
Trial 6= 0.0066s
Trial 7= 0.0054s
Trial 8= 0.0052s
84.0-cm long string;
Trial 1 = 0.4709 s
Trial 2 = 0.0124s
Trial 3= 0.0091s
Trial 4= 0.0100s
Trial 5= 0.0074 s
Trial 6= 0.0056s
Trial 7= 0.0057s
Trial 8= 0.0051s
Trial 9= 0.0040s
Lab 4: Conservation of energy
Note that for the online version of this lab exercise, data will be provided and students will NOT need to obtain the equipment listed. This equipment list and data collection instructions are provided so that students understand how the data was generated.
Purpose
To test whether or not conservation of energy is true for a pendulum.
Equipment used
A ring stand, a clamp with rod, string, a “photogate pendulum set,” a photogate timer on a photogate stand, a Vernier caliper, a ruler, and a meter stick.
Background
When a pendulum is pulled aside so that the pendulum bob is a height habove the bottom of its swing, all its energy will be initially in the form of gravitational potential energy. After the pendulum is released, it will have a speed vat the bottom of the swing due to the transfer of some potential energy to kinetic energy. The conservation of energy equation gives ½mv2=mgh, or more simply: v2=2gh.
Procedure and Data
In general, three different pendulums, made from different materials, are available for use in this experiment. Choose one and record your choice.
Choice of pendulum: _Aluminum_
The first step is to measure the width wof the selected pendulum using the Vernier caliper. This will be used later to calculate the speed of the pendulum as it passes through a photogate, which measures the time it takes, t, for the pendulum to pass through. The speed of the pendulum will be found using the formula v = w/t.
Width of pendulum: w= Click or tap here to enter text.
It will work best to convert the width you measured into meters:
Width of pendulum: w= Click or tap here to enter text.m
Set up the equipment so a pendulum hangs from the string in such a way that it blocks the photogate timer as shown to the right. Determine the length of the pendulum by measuring the distance between the top where the string is secured and a point in the middle of the pendulum bob. Record the length of the pendulum, L:
L = Click or tap here to enter text.cm
Then, remove the photogate temporarily to determine the height of the center of the pendulum above some reference point (probably the tabletop), hf. Be sure to record your result in units of meters, not centimeters.
hf= Click or tap here to enter text.m
Put the photogate back into place. Plug the photogate connector into the first digital channel of the Science Workshop interface box. Run the Capstone software. Your instructor will explain how to set up the software to use the photogate to determine the time tfor how long it takes for the pendulum to move across the photogate.
You will perform seven trials for each part below. In each trial, pull the pendulum to the side so that it starts at different heights h0. Record the height h0in the second column of the table. Release the pendulum from rest and record the time tthat the photogate timer records in the third column. Use this information to calculate vusing the formula v = w/t, and record the values in the fifth column. Then, square the quantities recorded in the fifth column to fill in the column labeled v2.
trial
h0
h = h0 – hf
t
v=w/t
v2 = (w/t)2
1
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
2
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
3
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
4
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
5
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
6
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
7
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Analysis
You will plot v2versus h=h0-hf. If the relation v2=2ghis true, then you should get a line with slope equal to 2g= 19.6 m/s2.
An Excel spreadsheet is embedded in this document for you to plot v2versush; that is, to plot v2on the vertical axis and hon the horizontal axis. To use it, double-click on the spreadsheet image. Once it is active, enter the time and displacement data in the spreadsheet cells, and the graph will be updated automatically. An equation of the best fit line through the data will appear in the graph. The value multiplying the “x” in the formula gives the slope. Clicking outside the Excel spreadsheet area will return control to the Word document.
Does the data fall on a line?Click or tap here to enter text.
What is the slope of the best fit line in the graph? slope = Click or tap here to enter text.
Again, if energy is conserved during the pendulum’s swing, the slope should agree with 2g= 19.6 m/s2. To assess the accuracy of the slope in your graph, calculate the percent error using
=Click or tap here to enter text.
A reasonable rule of thumb for answering the question: does the measured slope agree with the expected value of 19.6 m/s2is as follows:
If |% error| < 10% then answer ‘yes.’
If 10% < |% error| < 20% then answer ‘maybe:’ your experimental technique needs to be improved to know for sure.
If |% error| > 20 % then answer ‘no:’ your data does not support the theory.
Conclusion
Does the result of your data collection and analysis indicate the energy was conserved during the pendulum’s swing? Explain.
Click or tap here to enter text.
trial
h0
h = h0 – hf
t
v=w/t
v2 = (w/t)2
1
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
2
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
3
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
4
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
5
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
6
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
7
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Click or tap here to enter text.
Determine the width of the pendulum used in this lab from the Vernier caliper pictured below. 2 6 81 11011 How long a string would you like to use for the pendulum? Select one of the choices below by clicking on the text. 84.0-cm long strinExplanation / Answer
Q1. The width of the pendulum
main scale reading = 1.5 cm
vernier scale reading = 8
least count of vernier scale = least count of main scale/number of divisions on vernier scale = 0.1 cm / 10 = 0.01 cm
so the width of pendulum = 1.5 + 8 x 0.01 = 1.58 cm
--------------------------------------------------------------------------------------------------------------------------------------------------
Q 2. One should use the 56.0 cm long string because
0.0051
0.004
standard deviation for 56.0 cm long string is calculated as 0.0169
whereas stadard deviaiton for 84.0 cm long string is calcualted as 0.1545
So the stadard deviation is lesser in 56.0 cm long that means the data collected by 56.0 cm string are more precise.
56.0 cm long 84.0 cm long 0.0162 0.4709 0.019 0.0124 0.0118 0.0091 0.0089 0.01 0.0562 0.0074 0.0066 0.0056 0.0054 0.0057 0.00520.0051
0.004
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.