Throw a handful of rice on the courtyard and the pigeons come running. They peck so fast, and so exactly, one grain at a time. How do they find each grain? Why do their heads bob back and forth as they walk? Is a beak better than fingers for picking up scattered food?
Or think of the alarm clock (or the phone) that wakes you at six. Every morning it rings, and every morning you wake up. But how does a clock make a sound? How does the sound travel to your ears? How do you hear it at all?
Questions like these are where science starts. This unit shows you how a scientist turns a question into an answer that others can check, and how to write down what you did so that anyone can repeat it.
How scientific learning begins
Scientific learning begins with curiosity: the wish to know, which comes when you observe an object or an event. When you look carefully at the things around you, questions come to your mind: what is it, why does it happen, how does it work?
The careful, step-by-step study done to find the answers to such questions is called scientific learning. It involves thinking deeply, searching for the reasons, and finding answers you can trust.
The steps of scientific learning
A scientist doesn’t jump from a question straight to an answer. The work goes in steps, always in this order:
- Study the objects or events around us carefully (observe).
- Ask questions about the objects or events.
- Guess the possible answers to the questions.
- Test the guess using a suitable method.
- Record the data (the facts and measurements) the test gives.
- Analyze the data, and draw a conclusion.
- Prepare a report of the work.
A guess that can be tested has a name of its own, a hypothesis. If the test shows that the guess was wrong, that is not a failure: you have still found something out. You make a better guess and test again.
How does scientific learning about an object or an event begin?
Pick an answer to see why.
Sunita guesses that her plant is drooping because it hasn’t been watered for three days. Which step of scientific learning is this?
Pick an answer to see why.
Practical work of science
You can read that air takes up space, or that salt can be separated from salt water. But when you do it yourself, you see it, you remember it, and you know it is true. That is why practical work is so important in science.
Practical work is work done with real things, inside or outside a laboratory, about a definite topic. With practical work we can test a principle or a fact for ourselves. It takes several forms:
| Form of practical work | What you do | An example |
|---|---|---|
| Observing | look carefully, with your senses or with instruments | watching how a seed sprouts, day by day |
| Testing | do an experiment to check a guess or a fact | testing whether air contains oxygen |
| Surveying | collect information by asking many people or visiting many places | asking families in your area how they get rid of plastic waste |
| Project work | a longer study of one topic, often outside school | studying how clean a temple courtyard is kept |
| Model construction | make a model that shows how something works or looks | a bottle model of the lungs |
Which of these is practical work done in a laboratory?
Pick an answer to see why.
Report writing of practical work
When you finish a piece of practical work, you write a report. A report is the detailed description of the work: its objective, the materials needed, the method, the result, the conclusion and so on.
Why write a report at all? Because the work is only useful if others can know about it:
- to give the details of the practical work to the people concerned (your teacher, for example);
- to share what was found in the study or research clearly, so that everyone can understand it;
- to compare the result of the experiment with its objective (did we find out what we set out to?);
- to keep a record of the conclusion and of the problems met during the work.
The parts of a report
Reports can be laid out in slightly different ways, but most practical reports have these parts, in this order:
| Part | What it says |
|---|---|
| 1.Title | The name of the practical work. It comes first, because it tells the reader at once what the work is about. |
| 2.Objective | The purpose of the work: what you set out to find or show. Every practical work has a definite objective. |
| 3.Required materials | A list of everything used. From this list, anyone else can collect the same things and repeat the work. |
| 4.Figure | A neat, clear drawing of the set-up, with its parts labeled. |
| 5.Procedure (method) | The steps that were done, in order. |
| 6.Observation | What was seen or measured. Data are written down, often in a table, and sometimes shown in a graph. |
| 7.Analysis | The data are worked out (added, averaged, compared) to see what they show. |
| 8.Result | What the analysis shows. It tells whether the objective was met. |
| 9.Conclusion | The general fact that the result leads to. |
| 10.Precaution | The care to be taken during the work, to prevent accidents and to get a correct result. |
Why is the title written first in a report?
Pick an answer to see why.
Sample report 1: does air have a fixed volume?
A solid keeps its size and a liquid can hardly be squeezed at all, but the tiny particles of a gas have lots of empty space between them, so they can be pushed closer together. That is how a bicycle pump squeezes air into a tyre.
Sample report 2: is there oxygen in air?
Sample report 3: getting pure water from salt water
In distillation, what happens in the condenser?
Pick an answer to see why.
Project work
Model construction
Some things can’t be seen directly: the inside of your chest, the whole Solar System, an atom. Others are too big, too small or too slow to study. Scientists make models of them.
Model construction is the making of samples (models) of scientific processes and methods, materials, parts of living things, natural resources and so on, using materials found around you. With a model of the Solar System, an eclipse or the organs inside the body, we can study and show the parts we can’t see directly. A model makes the principles and facts of science clearer, so making models is an important part of scientific learning.
A collage model
A collage is a model made by sticking small pieces of paper (or seeds, cloth, leaves, bottle tops) onto a surface. A collage of photosynthesis might show the Sun’s rays falling on the leaves of a plant, carbon dioxide going into a leaf, oxygen coming out of it, and water going up from the roots. In the same way you can make collages of an atom, a food chain, the kinds of clouds, an ecosystem, or the Solar System with pictures of the Sun and the planets, printed or drawn and cut out.
The globe: a model of the Earth
You have seen a globe in class. It is a model of the Earth. On a globe you can see clearly that the Earth is round (a sphere), and that its axis, the line through the North and South Poles that it spins around, is tilted: it leans by 23.5° from the upright. A globe also shows the continents, the oceans and where the countries are.
Sample report of model construction: the lungs
The model works because the bottle is sealed. Pulling the sheet down makes the space inside the bottle bigger, so the air inside it is spread thinner and pushes less. The air outside now pushes harder, rushes in through the pipe and blows up the balloons. Letting the sheet go makes the space smaller again, and the air is squeezed out.
Your chest works the same way. When you breathe in, the dome-shaped diaphragm contracts and flattens, moving down, and the ribs move up and out: the chest gets bigger, and air rushes into the lungs. When you breathe out, the diaphragm relaxes and domes up again, and air is pushed out.
In the bottle model, what does the rubber sheet stand for?
Pick an answer to see why.
Exercise
1. Fill in the blanks
Use these words: continuous, principle, demonstrate, precautions, pattern, paragraph. (One word is not needed.)
Practical work helps to make the learned ……… clearer.
Answer
principle
To prevent possible accidents in laboratories, we should follow ……… .
Answer
precautions
We should write the report of practical work in a fixed ……… .
Answer
pattern
We can ……… scientific facts by making different models of science.
Answer
demonstrate
Learning is a ……… process.
Answer
continuous (it never stops: every answer leads to new questions). The word “paragraph” is not used.
2. Choose the correct option
a. How does the scientific learning process about an object or event begin?
Pick an answer to see why.
b. Which of these is practical work done in a laboratory?
Pick an answer to see why.
c. Which of these is written first in the report of a practical work?
Pick an answer to see why.
d. Why is the title written first in a report?
Pick an answer to see why.
3. Answer the following questions
What is scientific learning?
Answer
Scientific learning is the careful, step-by-step study done to find the answers to the questions (what? why? how?) that come to our mind when we observe an object or an event. It involves observing, asking questions, guessing answers, testing them, recording and analyzing the data, drawing a conclusion and writing a report.
How does scientific learning begin after seeing the objects or events around us? Explain with an example.
Answer
When we observe an object or an event carefully, we become curious, and questions come to our mind: what, why and how. Trying to answer them step by step is scientific learning.
Example: we wake up every morning to the sound of an alarm clock. Thinking about it, we ask: How does the clock make the sound? How does the sound reach our ears? How do we hear it? To answer, we can study how sound is made, test our guesses (for example, touch a ringing bell to feel it vibrate), record what we find, conclude that sound is made by vibrations that travel through the air to our ears, and write a report.
“Practical work plays an important role in science.” Justify the statement.
Answer
- Through practical work we test principles and facts ourselves, instead of only reading about them.
- Seeing and doing makes the learned principle clearer, and we remember it longer.
- It teaches skills: observing, measuring, using apparatus safely, recording data and writing reports.
- It is how new facts are found: every scientific fact was first discovered or checked by practical work, in or out of a laboratory.
- It can be done in many ways (observing, testing, surveying, project work and making models), so it fits every topic of science.
What is report writing? Why should we write the report of practical work?
Answer
Report writing is writing a detailed description of a piece of practical work after it is done: its title, objective, materials, figure, procedure, observation, analysis, result, conclusion and precautions.
We write reports:
- to give the details of the work to the people concerned;
- to share what was found clearly, so that everyone can understand it;
- to compare the result of the experiment with its objective;
- to keep a record of the conclusion and of the problems met during the work;
- so that others can repeat the work and check the result.
What should we take care of while writing a report?
Answer
- Write the parts in the right order, beginning with a clear title and objective.
- List all the materials, so anyone can repeat the work.
- Draw a neat, labeled figure.
- Write the procedure step by step, in the past tense (“The flask was heated”).
- Write the observations honestly, exactly as seen, even when they are not what you expected; use tables and units.
- When analyzing, check the calculations, take the average of repeated readings, and see whether the data really support the result.
- Make sure the result and conclusion answer the objective.
- Write the precautions taken.
- Keep it short, clear and tidy.
What should be included in the report of a practical work done inside a laboratory? Write in short.
Answer
- Title: the name of the work.
- Objective: its purpose.
- Required materials: the apparatus and substances used.
- Figure: a neat, labeled drawing of the set-up.
- Procedure: the steps done, in order, in the past tense.
- Observation: what was seen or measured, in a table or graph.
- Analysis: working out what the data show.
- Result: what the analysis shows; whether the objective was met.
- Conclusion: the general fact learned from the result.
- Precaution: the care taken to prevent accidents and errors.
4. Differentiate between
Practical work and a model
Answer
| Practical work | Model |
|---|---|
| Work done with real things, in or out of a laboratory, to test or find out a fact. | A sample made to show how something looks or works. |
| It is an activity: observing, testing, surveying, project work. | It is a thing that is made (making it is one kind of practical work). |
| It gives new data and results. | It shows a fact or process that is already known, especially one we can’t see directly. |
| e.g. distilling salt water | e.g. a globe, a bottle model of the lungs |
Observation and result
Answer
| Observation | Result |
|---|---|
| What is seen, heard or measured during the practical work. | What the observations, once analyzed, show. |
| It is written down while the work is done. | It is written after the analysis. |
| It is raw facts and data. | It tells whether the objective was met. |
| e.g. “The candle went out after a short time.” | e.g. “The candle needs the oxygen in the air to burn.” |
Practice every question in the book, and keep track of the ones you miss →