INVESTIGATIONS IN PHYSICS
The investigations included in this manual are both experimental and extended. They are experimental in the sense that they will be based on qualitative or quantitative observations of some phenomena and deductions made by you, the student. They are extended in that more time (at least a month) than a typical physics experiment would be required to undertake them.
Some samples included in this manual are structured. You are told exactly what to do and the questions you need to consider. Others are semi-structured. In these samples, the problem situation is described but the experimental design is left to you. However, some clues or questions to consider are included. This type of investigation provides a much needed challenge for you to think more independently and thereby gain satisfaction in achieving something of your own. Those included may be linked with the experiments and activities you may have done in class.
In a third type called open-ended investigations, only the problem is described. You are given the freedom of choosing the problem you wish to investigate. Or only the general topic is given and it is up to you to state the problem and design the method with which to solve the problem. A list of possible topics is provided.
Why do an experimental research project?
An experimental research project may provide the only real opportunity you will have in school of applying scientific approaches to a task. It will give you useful experience in mathematical and experimental analysis and introduce you to the work of a research scientist. These are experiences you will not usually gain in carrying out structured activities. You will be doing science rather than merely learning about science. And you will find that your ability to inquire – the essential elements of an investigation—will be very useful in your occupational, domestic and personal life.
If you do have the opportunity to choose your own topic and your own design, the experience will be unique for you. It will be your own research.
The objectives of requiring you to undertake investigations are for you to:1. Develop an understanding of the principles of experimental investigations in physics.2. Develop skills in practical investigations using the principles and methods of physics.
Your tasks then are to:
1. Identify a topic that interests you1. Decide how best to investigate the topic
2. Choose the appropriate instruments and tools and decide how best to use them
3. Cope with inevitable difficulties and if necessary redefine the objectives of your investigation
4. Analyze, evaluate and discuss your results
5. Write a report
The main value of the investigation lies not so much on the result but in the experience or journey as you work through the investigation.
After your work is completed and report written, you may have the opportunity of presenting your research to your own class, to other interested students or at the Science Fair of your school. You can join the competition and who knows, you may be a winner.
Selecting a research topic
There are three methods of arriving at a topic to be researched:
a) you propose a topic of your choice and have it approved by your teacher;
b) you select a topic from a list already approved by your teacher; and
c) you are assigned a topic by your teacher.
You will gain maximum satisfaction if method
(a) is used as the project will definitely be yours.
You can choose from five different types of investigation:
1. Designing and constructing a device.
This will involve designing and constructing a device and exploring the associated physics concepts and principles. Examples of devices that may be constructed are a thermistor temperature probe, a light meter, a water sensor, etc. It is important to remember that this is not merely a construction exercise. The emphasis must be on using physics ideas and methods to (a) analyze the purpose of the device,
(b) design a device which will achieve the purpose,
(c) construct the device and
(d) make it work as desired (that is test it and collect useful data).
2. Investigating the operation of a device
The emphasis in this type of investigation should be on investigating the device, not building it. Some typical questions that may be considered are: What does it do? How does it do it? How well does it do it? What sets the limits of its operation? How can it be improved?
3. Solving a scientific or technological problem
This type of investigation can become relatively open ended. It is important that the problem is specifically defined.
1. Investigating a physical phenomenon
This style of investigation allows you to examine physical phenomena such as the formation of rainbows, resolution of pin-hole cameras, production of sound by humans and by musical instruments, etc. Again this type of investigation can become relatively open-ended so you will need to limit the scope of the investigation to suit the time available.
2. Investigations that extend your understanding of a specific subject area by the process of gathering, collecting and synthesizing physics information and physics ideas from various sources. The topics chosen may be related to the following areas:
(a) everyday situations such as the use of remote controls in changing TV channels, digital
(b) other physics related forms of knowledge such as concepts in biophysics related to improving
(c) issues of social or personal significance such as the impact of compulsory use of seatbelts –
why was a law passed? How does it reduce/prevent injury in a vehicular accident? Or you
may be interested in the physics involved in their design or other physics issues associated
with safety on the road.
(d) technological applications such as the physics and technological applications of the laser;
technological advances in sporting equipment or in medical imaging.
Planning the investigation
1. Keep a logbook.
The logbook will be your essential companion from the selection of a topic to the completion of your investigation. In the planning stage use it to record possible topic, detailed plans and diagrams of experimental setup.
2. Generating suggestions -
a. Think beyond the laboratory. Consider your favorite sport, past time or hobby. Is there some aspect of it that is related to physics, which you can investigate?
b. Is there something at home or in your community/neighborhood that could form the basis of your investigation?
c. Is there something that you have studied in physics that you would like to study more deeply?
d. If it is a group project, brainstorm with the members of your group.
e. No one expects you to be an expert on a topic before you investigate or even afterwards. Consult resource materials or specialists before you can fully specify the actual problem you intend to solve.
3. Designing the investigation. Once you have proposed a topic, the next step is to devise a design or a method by which the investigation can be done. Brainstorm with your group alternative ways of tackling the investigation. Here are some points to consider:a. What specific questions do you want to answer?What do you think the answer will be? You are now generating the hypothesis or guess that you test. Stating an hypothesis may not be part of all investigations. However, you may have some expectations.
a. Do you have sufficient information to get underway? If not consult resource materials.
b. What equipment will be needed to carry out the investigation?a. How will you use the equipment to answer your question? What qualitative observations will be necessary? What measurements will you need to take? What will you do with these measurements? These are the questions at the heart of your experimental design.
1. Background reading and consulting. To come up with a suitable design you may need to do some background reading on your chosen topic. Ask help from your librarian or your teacher in using catalogues, computer databases, subject indices, abstracts and reviews. Record the resource materials/persons where you obtain useful information.
Carrying out the investigation
You have chosen a topic, specified exactly what you are to do, and decided how you are going to do it. The next step is to carry it out. At this point, the logbook is very important.
Most of the activities you have done consist of well-tested, structured experiments in which the desired results are reached smoothly. In an investigation this will not be so. Investigations may provide you with many unfamiliar experiences.
Here are some likely situations that you may encounter and ways of dealing with them.
(a) It would be normal to run into difficulties.
Using your imagination and perseverance in solving such difficulties is a very important part of research and a source of considerable satisfaction.
(b) Seek help if you need to from resource materials and people.
(c) Do not feel bad about making mistakes. It needs intelligence to recognize that you have made one.
(d) Once you are right into the project, you may find it necessary or desirable to modify, restrict, or extend the aims you have set for yourself. Be flexible but discuss any major change with your teacher.
(e) In some cases, it may not be possible to achieve the aim you set due to time and resources available. Realize that it is definitely a valuable exercise if you have attempted to work along logical lines and sensible use of your current scientific knowledge, the time allocated and the materials available.
(f) Beware of stockpiling. It is important to process data as soon as it has been collected. Such analysis will often suggest that certain readings need to be checked additional ones made or perhaps a new direction take.
Writing a research report
You may produce a report in three ways:
(a) a written report
(b) an oral report or
(c) a poster report.
Here are the most common parts of a research report. Your teacher will tell you which of these you will include in yours:
(a) Title page – includes the title of the investigation briefly stated, the names of the writers, the purpose for which the report is submitted, the date the research was completed.
(b) Abstract or synopsis- a statement of the specific problem investigated and the main conclusions reached
(c) Content- contains the details of the investigation. The main body covering the procedure, observations and deductions should appear subdivided into suitably labeled sections or chapters.
(d) Introduction – contains what motivated you to do the investigation or some background information
(e) Aim(s) – state exactly what you set out to investigate. If more than one, number them.
(f) Procedure, observations and deductions- the body of your report. This should includei. Clear explanation of what you attempted to doii. Description of materials usediii. Any hypotheses you set up and you went about testing themiv. Difficulties you encountered and how you overcome themv. Qualitative and quantitative observations madevi. Analysis of data and observationsvii. Conclusions made at various stages
(g) Summary of findings – here you should draw together the conclusions made at various stages, restating the findings, the limitations and possibly further associated research suggested.
(i) Reference or bibliography
(j) AppendicesPreparing your poster
The essential components include·
- A title.
- Name(s) of the researcher(s)·
- Aim(s) of the project·
- Arrangement of equipment, including a labeled diagram or photograph·
- A brief description of what you did·
- Your findings including significant tables and graphs if any and·
- Limitations of your results
In making your poster, consider·
- The maximum dimensions of an acceptable poster·
- How they can be attached to the display board or wall·
- Legibility from about 1 or 2 meters away·