CBSE class 9 Science practice paper by Jagran Josh will help students prepare for their periodic tests and upcoming mid-term exams. This practice paper is entirely solved which will make it easy for students to assess their preparation level and knowledge in order to perform well in their exams. This paper has been set as per the new pattern suggested by CBSE in latest CBSE Class 9 Science Syllabus for current academic session, 2019-2020. Students must solve this CBSE Science practice paper to get an idea of the question paper pattern and set of important questions from Class 9 Science subject.
A few sample questions from CBSE Class 9 Science Practice Paper 2019-2020 are given below:
Q. When heat is constantly supplied by a burner to boiling water, then the temperature of water during vaporisation :
(a) Rises very slowly
(b) Rises rapidly until steam is produced
(c) First rises and then becomes constant
(d) Does not rise at all
Ans. (d) Does not rise at all
Q. Among the following statements which one is incorrect?
(a) Golgi apparatus is involved with formation of lysosomes.
(b) Nucleus, mitochondria and plastid have DNA, hence they are able to make their own structural proteins.
(c) Lysosomes are called the suicide bags as they eat up their own cells.
(d) Cytoplasm is called known as protoplasm.
Ans. (d) Cytoplasm is called known as protoplasm.
Q. A plant body not differentiated into root, stem and leaves is termed as
Ans. (a) Thallus
Q. (a) When we open the cap of a cola drink (or any carbonated beverage), why does excess of bubbles come out?
(b) What are the physical states of dispersed phase and dispersion medium in a soft drink.
Ans. (a) A cola (or carbonated) beverage is produced by dissolving carbon dioxide in the drink
solution under pressure. Increase in pressure increases the solubility of gases. Therefore, more carbon dioxide dissolves at the higher pressure. When this pressure is suddenly released, e.g. by removing the cap of the bottle, carbon dioxide is less soluble, and it comes out in as bubbles from the solution.
(b) Dispersed phase: Gas (carbon dioxide gas)
Dispersion medium: Liquid (water)
Q. (a) Define the term scintillations?
(b) Write postulates of Rutherford’s Nuclear Model of atom?
Ans. (a) Scintillations are bright flashes produced through the α -particles in Rutherford model of an atom. When these particles passed through a slit and strikes against the gold foil, they get scattered and produce bright flashes known as scintillations.
(b) The main postulates of Rutherford’s Nuclear Model of atom are as follows:
(i) An atom is made up of two parts, nucleus and extra nuclear part. Nucleus is the center of the atom with positive charge. Extra nuclear part means the space around the nucleus in which the electrons are distributed.
(ii) The whole mass of the atom is located in the nucleus. Since the electrons have negligible mass, the mass of the atom is mainly due to protons.
(iii) The electrons revolve around the nucleus in well-defined orbits.
(iv) An atom is electrically neutral because number of protons and electrons is equal.
(v) Most of the atom is empty space.