Power Pole Observations
Find a power pole to observe.
What do you observe about the pole? Record your data.
Did you feel the surface? Did you smell the pole? Did you put your ear to the pole and hear anything? As an observer or as a scientist you need to use all your senses. Can you add more observations about the pole? If you have trouble making additional observations, the teacher may suggest some questions which will help your observation.
Once you observe the pole you can start to ask questions. A scientist is always asking questions. She or he ask herself or himself questions, ask other people questions, and try to answer the questions by experiments, reading, or talking with other scientists. Ask some questions about the pole and write them below.
After you have written your questions, look at the lists written by other students. Many of them asked different questions. Why?
Scientists often gather observations, questions and information from several people in order to get as many viewpoints as possible. Why may you observe or question in a way which is different from anyone else in your class?
The author is older than you are, about as old as your mother or father. Here are some of those questions. See if you asked some of the same questions? Read the questions below and check in the space to the left of the number of those questions similar to your questions.
________ 1. How tall is the pole?
________ 2. How long has the pole been in the ground?
________ 3. What kind of tree did the pole use to be?
________ 4. Who owns the pole?
________ 5. What do the wires on the pole do?
________ 6. Why are some wires larger than others?
________ 7. What gives the pole its color and strange smell?
________ 8. How deep is the pole in the ground?
________ 9. What makes the tiny holes in the sides of the pole?
________10. Is the top of the pole cut on a slant or not? Why?
________11. Why does the pole have a metal plate with numbers on it? What do the numbers mean?
The author could think of many more questions about the pole and so could you.
Many of us ask different questions about the same object because of our differences, our experiences, and our interests.
You have now seen one power pole and asked questions about it. Are all power poles alike? People in your class vary in age, in height and in hair color. power poles vary a great deal also. On your way home today look at poles and note below how other poles differ from the one you saw with your class.
How poles Differ from One Another:
Do poles differ from each other according to the use and makes of them?
Searching for Answers:
In science it is not enough to observe, ask questions, and notice differences. We want to be able to ANSWER the questions we ask.
There are many ways to answer my questions or your questions about the pole. Where do YOU suggest we start?
Check with other students to see if you agree as to where to look for answers.
Now it is time to answer questions which you have raised. For example: How tall is the pole? Each of you should try to guess. What is your guess? ________________ Remember to label your answer as to feet or inches. A number by itself is meaningless - be sure to label it inches, feet, miles or pounds.
One Method of Measuring:
There are several ways you can learn the height of the pole. Since it is dangerous to climb a pole (and against the law), we must use another way to decide how tall it is. One way is to use a person as a "measuring stick" near the pole. It is best to select a person who is three, four or five feet tall. This person stands next to the pole or in front of it. The rest of the class should move about 50 feet away from the pole. You can use a transparent grid or a ruler. Move to a spot where the student next to the pole measures exactly a certain number of squares on the grid, or one inch on the ruler. Count how many squares on the grid that the person is and how many squares there are from the ground to the top of the pole. If you used a ruler and the person standing beside the pole measured one inch, what did the pole measure in inches? If it takes six inches to reach the top of the pole and one inch represents a person, draw that to scale on a piece of paper. If the one inch = four feet tall, then the pole = 6 X 4 or 24 feet high. Measure a pole both ways, record the results on a piece of graph paper, and include any notes that might be helpful. What information do you need to remember?
Scientists always write down their results so that they won't forget them.
Another Method of Measuring:
Arithmetic is very important in science and nearly all scientists use arithmetic or other mathematics to help solve problems. If the pole is standing on flat ground and it is a sunny day, its shadow can be used to help learn how high the pole is. If the pole is surrounded by trees and the tree shadow does not allow us to see the pole shadow, we can not use this method unless the tree and the pole are exactly the same height.
The second method requires that an object whose height is known is already outside or can be taken outside and measure the length of its shadow.
A classmate whose height is known can be used as this object. Collect the following information:
Student height: _______________________
Student shadow length: ________________
Pole shadow length: ___________________
It is now possible to find the pole height using this information and the idea of proportion. The student's height is proportional to the student's shadow in the same way as the height of the pole is proportional to the pole's shadow's length.
Setting up the problem:
Use a sheet of graph paper and draw a line to scale to represent the height of the student and another perpendicular to it to represent the length of the student's shadow.
Use the same scale and draw another line to represent the length of the pole's shadow. Draw another line perpendicular to it to represent the height of the pole. Compare the number of units used to draw the student's shadow to the student's height. Use this relationship to draw the height of the power pole. You can then use the scale to find the pole's height.
Setting up a proportion mathematically:
Student height Student shadow length Pole height Poles hadow length 4 feet 3 feet ? 21 feet
Using your data from the previous page, find out the length of the pole (x).
Student height Student shadow length Pole height Poles hadow length ?
Finding Answers to Other Questions:
How long has the pole been there? Who owns it? How far apart are the poles and why are they this distance apart? Which wires are for telephones and which are for electricity? What are the other wires there to do? Do the wires carry sound or electricity?
Your teacher may annonunce some of the questions and help you get into small groups. Perhaps you and some of your friends can find out the answers.
Possible information sources: (hint below)
Information on power poles is rather difficult to locate. Did you try the telephone company, electric company, dictionary, encyclopedia or other reference sources? For some problems there is very little information in books and you must go to people or experiment to find answers. Don't be too surprised if people working for companies which use the pole don't know too much about your questions. You may be the first person that asked them these questions.
From the information you and your classmates have collected go back and answer your own questions and those of the author. Write a paragraph or two about the pole and include information about the pole which answers these questions. You might like to take photographs of poles, or make a bulletin board or poster display of your findings.
Dr. Robert Sweetland's Notes ©