Class: 9 Subject: Science
Chapter: Exploration: Entering the World of Secondary Science
Maximum Marks: 50
Suggested Time: 1 Hour 30 Minutes
Section A — Objective Questions
10 × 1 = 10 marks
Q1. Which is the most important feature of a useful scientific model?
a) It contains every possible detail.
b) It focuses on details relevant to the question being studied.
c) It never changes.
d) It must be a physical object.
Q2. The SI unit of mass is:
a) gram
b) kilogram
c) pound
d) tonne
Q3. Scientific symbols are useful because they:
a) make scientific communication precise
b) replace all observations
c) are different in every country
d) remove the need for units
Q4. Which statement about scientific theories is correct?
a) They are guesses.
b) They are explanations supported by evidence.
c) They cannot change.
d) They are personal beliefs.
Q5. Which is an example of an approximate question?
a) What is the exact mass of a medicine tablet?
b) How much rice might a family need in a month?
c) What is the exact temperature in a laboratory?
d) What is the exact length of a metal rod?
Q6. If two scientists use different units for the same quantity, standard units help them:
a) avoid comparison
b) compare their results consistently
c) make different conclusions automatically
d) avoid measurement
Q7. Which statement represents evidence-based prediction?
a) “It will rain because I feel that it will.”
b) “It will rain because the humidity, pressure and wind pattern are similar to conditions before earlier rainfall.”
c) “It will rain because everyone says so.”
d) “It will rain because rain always occurs.”
Q8. A principle is generally:
a) a broad idea useful for understanding a situation
b) an unsupported guess
c) a measurement unit
d) a laboratory instrument
Q9. Which branch of science mainly studies living organisms?
a) biology
b) physics
c) astronomy only
d) mathematics
Q10. Why do different branches of science overlap?
a) Nature itself is divided into school subjects.
b) Real-world problems often involve several kinds of scientific ideas.
c) Scientists cannot work independently.
d) Mathematics is the only science.
Section B — Very Short Answer
5 × 2 = 10 marks
Q11. What is meant by an assumption in a scientific model?
Q12. Why is the colour of a bicycle usually irrelevant when modelling travel time?
Q13. What is the difference between observation and prediction?
Q14. Give one example of a situation where an approximate answer is useful.
Q15. Name any two branches of science.
Section C — Short Answer Questions
4 × 3 = 12 marks
Q16. Explain why scientific language needs to be precise.
Q17. Why is a theory not the same as a guess?
Q18. Explain why standard units are important in international scientific communication.
Q19. What should a scientist do if a prediction does not match the observation?
Section D — Application-Based Questions
2 × 4 = 8 marks
Q20. A student wants to estimate how many steps they take in a day. They walk about 100 steps in 1 minute and are active for about 90 minutes during the day.
a) Estimate the number of steps taken.
b) Why is the answer approximate?
c) Give one factor that could make the actual number different.
Q21. A student builds a model of a cricket ball being hit for a six.
a) Name two factors that are important in predicting whether the ball will cross the boundary without bouncing.
b) Name two details that could be ignored in a simple model.
c) Why is it acceptable to ignore them?
Section E — Long Answer Questions
2 × 5 = 10 marks
Q22. Explain the difference between laws, theories and principles with suitable examples.
Q23. Explain how mathematics supports scientific thinking rather than merely helping with calculations.