KENDRIYA VIDYALAYA STEEL PLANT - CLASS IX SCIENCE SAMPLE PAPER
SET - B (Total Marks: 40)
Section A: MCQs (10 x 1 = 10 Marks)
1. Which isotope is used as the standard reference for measuring atomic masses?
B) Oxygen-16
C) Hydrogen-1
D) Nitrogen-14
Click to View Answer
Answer: A (Carbon-12)
2. What is the valency of Carbon?
B) 3
C) 4
D) 1
Click to View Answer
Answer: C (4)
3. The mass of a proton is approximately how many times that of an electron?
B) 2000
C) 500
D) 12000
Click to View Answer
Answer: B (2000)
4. The chemical symbol for Sodium is:
B) So
C) Na
D) Sd
Click to View Answer
Answer: C (Na)
5. Newton concluded that all objects in the universe attract each other with a force called:
B) Gravitational force
C) Friction
D) Centrifugal force
Click to View Answer
Answer: B (Gravitational force)
6. Weight of an object on the moon is ____ its weight on Earth.
B) 1/6th
C) 6 times
D) Equal to
Click to View Answer
Answer: B (1/6th)
7. Thrust acting on unit area is called:
B) Volume
C) Pressure
D) Work
Click to View Answer
Answer: C (Pressure)
8. The SI unit of pressure is:
B) Pascal
C) Joule
D) Watt
Click to View Answer
Answer: B (Pascal)
9. What is the correct formula for Work Done?
B) W = F × s
C) W = m × g
D) W = P / t
Click to View Answer
Answer: B (W = F × s)
10. The sum of Potential and Kinetic energy is called:
B) Light Energy
C) Mechanical Energy
D) Heat Energy
Click to View Answer
Answer: C (Mechanical Energy)
Section B: Case Based Questions (2 x 4 = 8 Marks)
Case 1: Dalton's Atomic Theory.
John Dalton provided the basic theory about the nature of matter. He stated that all matter is composed of small particles called atoms. His postulates explained the laws of chemical combination, including the Law of Conservation of Mass and Law of Definite Proportions.
Click to View Sub-questions & Answers
2. Which postulate results from the Law of Conservation of Mass? Ans: Atoms are indivisible and cannot be created or destroyed in a reaction.
3. What can you say about atoms of a given element? Ans: They are identical in mass and chemical properties.
4. In what ratio do atoms combine to form compounds? Ans: They combine in the ratio of small whole numbers.
Case 2: Law of Conservation of Energy.
Whenever energy gets transformed, the total energy remains unchanged. Energy cannot be created or destroyed; it only changes from one form to another. This law is valid in all situations and for all types of transformations.
Click to View Sub-questions & Answers
2. What happens to total energy during a transformation? Ans: The total energy before and after the transformation remains the same.
3. What is the potential energy of a mass 'm' at height 'h'? Ans: It is calculated as mgh.
4. What is the kinetic energy of a stationary object? Ans: It is zero because its velocity is zero.
Section C: Match the Following (4 x 1 = 4 Marks)
| Column A | Column B |
|---|---|
| 1. Anion | A. Henry Cavendish |
| 2. Isobars | B. 1 Newton × 1 Metre |
| 3. G discovered by | C. Negatively charged ion |
| 4. 1 Joule | D. Same A, Different Z |
Click to View Answer
Answer: 1-C, 2-D, 3-A, 4-B
Section D: Short Answer Questions (5 x 2 = 10 Marks)
1. What is a polyatomic ion? Give an example.
Click to View Answer
A group of atoms carrying a net charge is known as a polyatomic ion.
Example: Nitrate (NO₃⁻) or Hydroxide (OH⁻).
2. Give the symbols for Aluminium and Chlorine.
Click to View Answer
The chemical symbol for Aluminium is Al.
The chemical symbol for Chlorine is Cl.
3. Define Buoyancy.
Click to View Answer
It is the upward force exerted by a fluid on an object immersed in it.
This force is also known as upthrust or buoyant force.
4. Define 1 Watt of power.
Click to View Answer
1 Watt is the power of an agent which does work at the rate of 1 Joule per second.
It is the unit used when consumption of energy is 1 J/s.
5. State one use of Isotopes.
Click to View Answer
An isotope of Uranium is used as a fuel in nuclear reactors.
Alternatively, an isotope of Cobalt is used in the treatment of cancer.
Section E: Long Answer Questions (2 x 4 = 8 Marks)
1. State the Universal Law of Gravitation and explain its importance.
Click to View Answer
Law: Every object attracts every other object with a force proportional to the product of their masses and inversely proportional to the square of the distance between them.
Importance 1: It explains the force that binds us to the earth.
Importance 2: It explains the motion of the moon around the earth and planets around the Sun.
Importance 3: It explains the occurrence of tides due to the moon and the Sun.
2. Discuss the interconversion of various energy forms with examples.
Click to View Answer
1. Energy can be changed from one form to another, such as potential to kinetic.
2. Example: In a bow, potential energy of the stretched string changes to kinetic energy of the arrow.
3. Example: During free fall, gravitational potential energy transforms into kinetic energy.
4. Example: Green plants convert light energy into chemical energy during photosynthesis.
No comments:
Post a Comment
Thank you