Question 1

Science in secondary education emphasizes not only what we know but also how we know it. Which of the following best describes this emphasis?

Accepted Answer

Observing, measuring, modeling, and testing scientific ideas — Secondary science focuses on deep exploration, which includes careful observation, measurement, building models to represent complex systems, and testing ideas through experiments rather than just memorizing facts.

Question 2

The magnifying glass and the compass on the textbook pages symbolize which two aspects of scientific exploration?

Accepted Answer

Observation and direction in scientific inquiry — The magnifying glass represents careful observation, noticing patterns and details, while the compass symbolizes direction, choosing appropriate models and questions in scientific exploration.

Question 3

Why do scientists use models in their study of natural phenomena?

Accepted Answer

To simplify complex systems by focusing on important features — Models are simplified representations that focus on key aspects of complex systems to make them easier to study and understand, deliberately ignoring less important details.

Question 4

In the example of modeling a cricket shot, which of the following details would be ignored in a simple model to predict if the ball crosses the boundary?

Accepted Answer

Brand of the bat — The brand of the bat does not affect the ball's trajectory significantly and can be ignored in a simple model, whereas mass, speed, and direction are important. Air resistance may also be ignored for simplicity.

Question 5

Activity 1.1 asks students to model the time taken to ride a bicycle from school to home. Which of the following details is most appropriate to keep in the model?

Accepted Answer

The distance between school and home — Distance is a key factor affecting travel time, while color, helmet brand, or number of trees do not significantly affect the time taken and can be ignored in a simple model.

Question 6

Why is it important to use standard units like kilograms and meters in scientific measurements?

Accepted Answer

To ensure measurements are consistent and comparable worldwide — Standard units allow scientists and people everywhere to understand and compare measurements without confusion, avoiding errors like the airplane fuel miscalculation incident.

Question 7

In the airplane fuel incident, what was the main cause of the fuel shortage during flight?

Accepted Answer

The ground crew used fuel density in pounds per litre instead of kilograms per litre — A unit conversion error caused the ground crew to underestimate the fuel needed, leading to a shortage and emergency landing.

Question 8

The speed of light is denoted by the symbol 'c'. From which language does this symbol originate and what does it mean?

Accepted Answer

Latin, meaning speed — The symbol 'c' comes from the Latin word 'celeritas' which means speed, representing the speed of light as a physical constant.

Question 9

Which of the following best describes a scientific law?

Accepted Answer

A regular pattern observed in nature often expressed mathematically — A scientific law describes consistent natural patterns, such as Newton's laws of motion, and is often expressed using words or equations.

Question 10

Assertion (A): A scientific theory is an untested guess.
Reason (R): Theories are explanations based on careful testing and evidence.
Choose the correct option.

Accepted Answer

D — Assertion is false because a scientific theory is not an untested guess; it is a well-tested explanation. Reason is true as theories are based on evidence and testing. Hence, D is correct.

Question 11

Which of the following is NOT a reason why weather forecasts sometimes fail?

Accepted Answer

Scientists use unreliable instruments — Modern instruments are reliable; forecast failures are due to the chaotic nature of weather and sensitivity to initial conditions.

Question 12

Fig. 1.2 shows a total solar eclipse where the moon blocks the sun's light creating a shadow on Earth. Using this, why is the claim that 'food becomes harmful during an eclipse' scientifically incorrect?

Accepted Answer

Because an eclipse is just a shadow and does not cause temperature or chemical changes in food — The eclipse is a temporary shadow causing no physical, chemical, or biological change to food; hence, the claim is false.

Question 13

Estimate the approximate number of breaths a person takes in one day if the resting breathing rate is about 12 breaths per minute.

Accepted Answer

17280 breaths — Given: Breaths per minute = 12
Minutes per day = 60 × 24 = 1440
Find: Total breaths per day
Formula: Total breaths = breaths per minute × minutes per day
Solution: 12 × 1440 = 17280 breaths
Answer: Approximately 17280 breaths per day
Note: Some estimates use 12–15 breaths per minute leading to 17280–21600 breaths.

Question 14

Using the balloon example, estimate the total volume of air breathed in one day if one breath is about 0.5 litre and a person takes 12 breaths per minute.

Accepted Answer

8640 litres — Given: Breaths per minute = 12
Volume per breath = 0.5 litre
Minutes per day = 1440
Find: Total volume of air per day
Formula: Total volume = breaths per minute × volume per breath × minutes per day
Solution: 12 × 0.5 × 1440 = 8640 litres
Answer: Approximately 8640 litres per day
Note: This matches the balloon example estimate.

Question 15

Fill in the blank: In science, the process of making a tentative explanation based on observations, which can be tested through experiments, is called a _____.

Accepted Answer

hypothesis — A hypothesis is a tentative explanation formulated based on observations that can be tested through experiments to support or refute it.

Exploration: Entering the World of Secondary Science

Exploration: Entering the World of Secondary Science — Study Notes

Introduction

What is Science?

Scientific Methods

Practice Questions — Exploration: Entering the World of Secondary Science

All 13 Chapters in Exploration