Jagranjosh.com, India’s leading education portal, presents CBSE Class 9 Science Solved Practice Paper for Sumamtive Assessment-II, 2016-17. This practice paper is specially prepared by the subject experts after the brief analysis of previous year question papers. The paper contains entirely fresh questions picked from the most important topics of Science. All the questions are provided with an apt explanation. This paper will help the students in understanding the depth with which a topic should be studied in order to prepare in a more effective way to get the desired results.
Importance of CBSE Class 9 Science Practice Paper, 2016 -2017:
This Science SA – II Practice Paper for CBSE Class 9, is set as per the latest CBSE exam pattern and aims at helping the students to prepare for the exam more effectively so as to get the desired results.
Unique solutions to all the questions are provided to give the students a clear idea about what and how much must be written in the Class 9th Science SA – II Examination 2016 – 17 to score optimum.
This Practice Paper will Help You:
• understand the latest examination pattern
• get aquainted to the important topics to be studied for SA – II Science Exam
• learn to give proper explanations to the questions
Few sample questions from the Question Paper are given below:
Q. Give two examples of class amphibia.
Frog and salamander.
Q. (a) Define atomicity.
(b) State the atomicity of the following molecules
(i) Oxygen (ii) Phosphorus
(iii) Sulphur (iv) Argon
(a) The number of atoms in a molecule of an element is called its atomicity.
(b) Atomicity of given molecules is:
(i) Oxygen, O2 = 2
(ii) Phosphorous, P4 = 4
(iii) Sulphur, S8 = 8
(iv) Argon, Ar = 1
Q. What is SONAR? Explain its use.
Sonar is an acronym for Sound Navigation And Ranging. Sonar is a device installed in a boat or a ship that consists of transmitter and detector. The transmitter produces and transmits ultrasonic waves. These waves fall on the seabed and get reflected back which is then sensed by the detector. The job of the detector is to convert ultrasonic waves into the electrical signals.
The uses of sonar are to determine depth of sea, locate sunken ships, cargos, icebergs and submarines.
Q. State the major characteristics considered for classifying the organisms.
There are 3 major characteristics for classifying organisms
(i) Nature of cell: It includes presence or absence of membrane bound cell organelles, which is the fundamental characteristic for classification. On this basis, the organism are classified as eukaryotes and prokaryotes.
(ii) Cellularity: Single cell and multiple cells are the second characteristics. Unicellular organism are made of one cell and multicellular are made of many cells.
(iii) Mode of nutrition: The ability to manufacture their own food or get them from other organisms also is a distinguishable feature.
Q. Raju used to supply milk in a locality. Though he claimed that he supplied pure milk, many people complained that his supply contained adulterated milk. To help people in his neighbourhood, Sourabh put the milk to test in a lactometer and proved Raju wrong.
(i) What is a lactometer?
(ii) State the principle on which a lactometer works.
(iii) What values are exhibited by Varun?
(i) A lactometer is a device that is used to measure the density of milk. It can be used to test milk adulteration.
(ii) A lactometer works on the principle of specific gravity of milk.
(iii) Sourabh is an alert and caring citizen. He is aware that the public is being fooled by Raju. Therefore, tested the milk to prove that Raju is lying.
Q. What is audible range of frequency for human beings? How does bat catch its prey?
Audible range of frequency of humans is 20 Hz to 20, 000Hz.
Bats can emit ultrasonic waves from their mouths, which when touch the prey, get reflected back to the bat. By hearing these echoes off of objects around them, bats can adjudge the distance and direction of the prey thus find out the way to navigate and capture their food.
Q. (a) Briefly explain why some objects sink but others float when immersed in a liquid.
(b) When a boat is partially immersed in water, it displaces 600 kg of water. How much is the buoyant force acting on a boat in Newton? (Take g = 10 m/s2)
(a) Objects having density more than that of density of liquid will sink in the liquid when immersed whereas the objects having density lower than that of the liquid will float when immersed in that liquid.
(b) Mass of water displaced by boat, m = 600 kg
Acceleration due to gravity, g = 10 m/s2
Bouyany force acting on an object in water is equal to the weight of water displaced by that object.
Now weight of water displaced by boat = m × g
= 600 × 10= 6000 N
Q. Which of the following is a warm - blooded animal?
(a) Liver fluke (b) Human being
(c) Draco (d) Salamander
Explanation: Humans are endotherms or warm blooded animals that can maintain their body temperature when external temperature changes.
Q. Ammonium chloride sublimates on heating. It means that on heating ammonium chloride:
(a) First melts at its melting point and then changes into a gas at its boiling point
(b) Directly changes from solid to vapours without melting.
(c) Loses its water of crystallization
(d) Condenses from the gaseous state to the liquid state
Explanation: Ammonium chloride decomposes into the gases ammonia and hydrogen chloride upon heating.
Q. When dipped in a fluid, name the factor on which the loss in weight of a solid depends. Name the two forces which act upon the solid dipped in the fluid.
Loss of weight of a solid in a fluid depends on the density of liquid and volume of the body. The two forces that act upon the solid dipped in the fluid are:
- Actual weight of the body acting vertically downwards
- Upward thrust or buoyant force acting vertically upwards.