Chapter 1 Exploring the Investigative World of Science

Meaning of Science

Science is a systematic study of the natural world based on observation, experimentation, and logical reasoning. It helps us understand how things work and solve problems using evidence. It also refers to the organized body of knowledge gained through scientific methods.

Characteristics of scientific methods

1. A. Empirical Evidence: Knowledge is obtained from observable, measurable, and universally acceptable data gathered through direct experimentation or observation instead of mere belief.
   Example: A scientist tests whether plants grow faster with sunlight by measuring the height of plants kept in sunlight and comparing them with plants kept in darkness.
2. Replicability:Scientific methods and experiments must be transparent and repeatable. If a specific study is conducted under the same conditions, it should provide consistent results throughout the universe.
   Example: If different laboratories around the world heat water to 100°C at normal atmospheric pressure, the water should boil each time under the same conditions.
3. Objectivity:Objectivity refers to the state of being impartial, neutral, and free from personal biases or emotional influence.
   Example: A doctor testing a new medicine records both positive and negative effects of the drug instead of only reporting successful cases.
4. Systematic & Controlled:Scientific methods follow structured procedures where researchers carefully design experiments and control variables to establish clear cause-and-effect relationships.
   Example: To test the effect of fertilizer on plant growth, a researcher keeps the amount of water, sunlight, and soil the same for all plants while changing only the fertilizer amount.
5. Predictability:Scientific theories are used not only to explain current phenomena but also to make accurate, reliable predictions about future events.
   Example: Weather scientists use meteorological data to predict rainfall or storms several days in advance.

Branches of Science

1. Physics: Physics is the study of matter, energy, force, motion, light, sound, electricity, and related phenomena.

Examples:

• Motion of vehicles on roads
• Electricity used in homes
• Mobile phone and wireless technology
• Sound produced by speakers
• Light from bulbs and the Sun

1. Chemistry: Chemistry is the study of substances, their composition, properties, and chemical reactions.

Examples:

• Cooking food involves chemical changes
• Preparation of medicines
• Rusting of iron
• Burning of fuels
• Mixing vinegar and baking soda

1. Biology : Biology is the study of living organisms and life processes.

Examples:

• Study of the human body
• Growth of plants and animals
• Diseases and health care
• Photosynthesis in plants
• Human digestion and respiration

Importance of Science in Daily Life

Science plays an important role in modern life by improving comfort, communication, health, transportation, and productivity.

1. In Transportation

Science has made travel faster, safer, and more convenient.

Examples:

• Cars, buses, trains, and airplanes
• GPS navigation systems for finding routes
• Electric vehicles and fuel-efficient engines

2. In Communication

Science and technology help people communicate instantly across the world.

Examples:

• Mobile phones for calls and messages
• Internet for online learning and communication
• Satellites for television and global communication

3. In Medicine

Scientific discoveries help prevent and treat diseases, improving human health.

Examples:

• Vaccines to prevent diseases
• X-rays, MRI scans, and surgeries
• Antibiotics and modern medicines

4. In Agriculture

Science increases food production and improves farming methods.

Examples:

• Fertilizers that improve soil fertility
• Irrigation systems for watering crops
• Hybrid seeds that produce better yields

5. In Household Activities

Science makes daily household work easier and saves time.

Examples:

• Refrigerators for food preservation
• Washing machines for cleaning clothes
• Microwave ovens for quick cooking and heating foo

Scientific Attitude

A scientific attitude means thinking logically, questioning ideas, and seeking evidence before accepting anything as true.

Characteristics of a Scientific Attitude

• Curiosity: Desire to learn and ask questions
• Open-mindedness: Willingness to consider new ideas and evidence
• Honesty: Reporting facts truthfully without changing results
• Critical Thinking: Analyzing information carefully before making conclusions
• Patience: Taking time to observe, test, and verify results

Scientific Method

The scientific method is a step-by-step process used to solve problems and discover new knowledge.

Steps in the Scientific Method

1. Observation: Carefully noticing events or phenomena. Example: Plants grow better in sunlight.
2. Asking Questions: Questions arise from observations. Example: Why do plants need sunlight?
3. Forming a Hypothesis: A hypothesis is a possible explanation or prediction. Example: Plants grow faster when they receive more sunlight.
4. Experimentation: Testing the hypothesis through experiments.

Example: Growing one plant in sunlight and another in darkness to compare growth.

5. Collecting Data: Recording measurements and observations. Example: Measuring plant height every day.
6. Analysis: Studying data to identify patterns or conclusions. Example: Comparing the growth of both plants.
7. Conclusion; Accepting or rejecting the hypothesis based on the results. Example: Concluding that sunlight helps plants grow faster if the sunlit plant grows taller.

Observation in Science

Observation is the foundation of science because scientific investigations begin by carefully observing natural events and phenomena. Scientists use their senses and instruments to gather information and identify problems for study.

Types of Observation

1. Qualitative Observation

Qualitative observation describes the qualities or characteristics of an object using the senses. It does not involve numbers or measurements.

Examples:

• Color of a flower is red
• Smell of perfume is pleasant
• Shape of a leaf is oval

2. Quantitative Observation

Quantitative observation uses numbers or measurements and can be measured accurately.

Examples:

• Temperature = 30°C
• Height = 150 cm
• Mass = 5 kg

Measurement in Science

Measurement makes scientific study accurate and reliable.

SI Units (International System of Units)

Quantity	SI Unit	Symbol
Length	metre	m
Mass	kilogram	kg
Time	second	s
Temperature	kelvin	K
Electric current	ampere	A

Importance of Measurement

• Ensures accuracy in experiments
• Allows comparison of results
• Helps repeat experiments correctly

Laboratory Safety Rules

Safety is essential while performing scientific experiments.

Important Rules

• Wear safety goggles and gloves
• Handle chemicals carefully
• Do not taste chemicals
• Keep the laboratory clean
• Follow teacher or instructor instructions

Role of Scientists

Scientists investigate nature, conduct experiments, and develop new technologies to improve human life.

Famous Scientists

• Isaac Newton — Laws of motion and gravity
• Albert Einstein — Theory of relativity
• Marie Curie — Radioactivity
• C. V. Raman — Raman Effect

Science and Technology

Science and technology are closely related.

• Science explains natural phenomena.
• Technology applies scientific knowledge for practical use.

Examples

• Electricity → Electric appliances
• Biology → Medical equipment
• Space science → Satellites and rockets

Important Terms

Term	Meaning
Hypothesis	A testable prediction
Experiment	A scientific test
Observation	Careful noticing
Data	Information collected
Conclusion	Final result of investigation

Diagram: Scientific Method

Observation

↓

Question

↓

Hypothesis

↓

Experiment

↓

Data Collection

↓

Analysis

↓

Conclusion

 

INTEXT SOLUTIONS

Probe and Ponder (Page 1)

Question 1. Is there a question that makes you curious about the world?

Write it here! __________________________________
Sample Answers:

• Why does rice cook faster in a pressure cooker than in an open vessel?
• Why do cut apples turn brown after some time?
• Why does ice melt faster in warm water than in cold water?
  (Questions may vary)

Question 2.Why has nature created such a vast variety of plants and animals? (Page 1)
Answer: Nature has created a vast variety of plants and animals to maintain balance in ecosystems.

Question 3. What symbols are used in the book to represent deep knowledge and imagination,respectively? (Page 2)
Answer: A root at the bottom of the left pages represents deep knowledge, and a kite on top of the right pages represents curiosity and imagination.

Question 4. What does it mean to investigate like a scientist? (Pages 2, 6, 7)
Answer: It means asking specific questions, designing controlled experiments, making observations, measuring, and drawing conclusions one step at a time.

Question 5.What is the importance of curiosity in Science? (Page 2)
Answer: Curiosity is the starting point of Science. Asking “why” and “how” helps us begin investigations and discover new knowledge.

Question 6.What scientific topics will be covered in the textbook this year? (Pages 3, 4, 5)
Answer: The following chapter will be covered this year:

• Microbes and health
• Electricity and its effects
• Force, pressure, and motion
• Particles, elements, compounds, mixtures
• Light: reflection, mirrors, and lenses
• Phases of the Moon and calendars
• Ecosystems and climate change

Question 7. How can human activity affect the Earth’s climate? (Page 5)
Answer: Human actions like burning fossil fuels and deforestation can change the Earth’s temperature, disrupt climate patterns, and cause serious consequences.

Question 8.Why is one side of a puri thinner than the other? (Page 6)
Answer: When a puri is fried, steam forms inside, expanding and pushing one side more, making it thinner. This can depend on dough thickness, temperature, or how it’s dropped in oil.

Question 9. Do puris puff better when made fresh or from stored dough? (Page 7)
Answer: Puris usually puff better when made from fresh dough rather than stored dough. Fresh dough has the right moisture and softness, which helps the puris puff up properly. Stored dough often becomes dry and hard, making it difficult for the puris to puff up well.

Question 10. What is a systematic investigation? (Page 7)
Answer: A method where only one variable is changed at a time, others are kept constant, and careful observations and records are mad

ADDITIONAL QUESTIONS

Multiple choice questions.

Q1. Which of the following best describes the ‘investigative world of science’ as presented in this chapter?

(a) Learning facts and memorizing them

(b) Asking questions, observing, doing experiments, and finding answers

(c) Only reading books and watching videos

(d) Remembering names of scientists

Answer: (b) Asking questions, observing, doing experiments, and finding answers

Q2. What do the symbols of the root and the kite found in the textbook represent?

(a) Food and play

(b) Experiment and memory

(c) Foundation of knowledge and flight of ideas

(d) Growth and height

Answer: (c) Foundation of knowledge and flight of ideas

Q3. According to the chapter, which step should be followed first in scientific investigation?

(a) Explaining your observations

(b) Designing an experiment

(c) Making observations

(d) Asking a question out of curiosity

Answer: (d) Asking a question out of curiosity

Very Short Answer

Q1. Define “systematic investigation” as mentioned in the chapter.

Answer: Systematic investigation is a process in which a person explores, observes, experiments, and records results one step at a time to find answers to scientific questions.

Q2. What is the first sign of scientific curiosity, according to the chapter?

Answer: The first sign of scientific curiosity is asking “Why?” and “How?” questions about everyday phenomena in the world around us.

Q3. Give an example of a question a young scientist might ask, as suggested by the chapter.

Answer: An example is, “Why does dough rise when it is heated?” or “Why do puris puff up unevenly in oil?”

Short Answer Questions

Q1. Explain why it is important to change only one condition at a time in a simple science experiment, as described in the chapter.

Answer: Changing only one condition at a time allows us to see clearly how that specific change affects the result. This helps us make accurate conclusions about what causes a certain effect, as all other variables remain the same.

Q2. How do the concepts of roots and kites help students think like scientists as per the chapter?

Answer: The root symbolizes a strong foundation in observation and tradition, while the kite represents curiosity and creative thinking. This balance encourages students to thoughtfully observe and explore new ideas—both are essential for scientific investigation.

Q3. Give two reasons why investigation in science is relevant in everyday life, according to the chapter.

Answer: First, scientific investigation helps us solve real-world problems, such as understanding why dough rises. Second, it encourages curiosity, which can lead to discoveries that improve our lives, like developing healthy habits or understanding weather events.

True or False Questions

Q1. The process of scientific investigation is only possible in a laboratory.

Answer: False

Q2. The reason for one side of a puri being thinner than the other is completely understood by scientists.

Answer: False

Q3. Careful observation and asking questions are both important for doing science.

Answer: True

Fill in the Blanks Questions

Q1. The bending of light explains why we see an image in a ________.

Answer: shiny metal spoon

Q2. The ________ at the bottom of the textbook page symbolizes the foundation of knowledge.

Answer: root

Q3. On the right-hand pages, at the top corner, there is a ________, representing curiosity and exploration.

Answer: kite