CBSE Class 9   CBSE Class 9 Science

State the three rules proposed by Bohr and Bury, regarding the distribution of electrons in different orbits of an atom (2)
Explain why the number of atoms in one mole of hydrogen gas is double the number of atoms in one mole of helium gas? (2)
Calculate the ratio of the gravitational acceleration of the Earth due to the Sum with that of the Earth due to the Moon (2)
Explain, why filter paper cannot be used to separate colloids? (2)
Transportation of food from leaves to other plant parts (2)
Name the protective tissues of plants. Explain them in detail with suitable examples (2)
What will be the work done by him? (2)
Write down the applications of ultrasonic waves (2)
Differentiate between thrust and pressure. How does 1 Pascal differ from 1 Newton? (2)
What values do you observe in the patient? (2)
The distance travelled by the object in 10 s (2)
What could happen if the needle was not sterilised? (2)
Define the term inertia and its types. A ball and a car, which one has greater inertia? (2)
Nitrogen-fixing bacteria are found in which plants and why? (2)
Illustrate carbon cycle existing in nature (2)
Discuss how can we contribute in the reduction of water pollution (2)
If the cells of onion peel and RBCs are separately kept in hypotonic solution. What will take place? (2)
Can you suggest a probable reason for this observation? (2)
Calculate the distance between buildings (2)
Find out wavelength, frequency and time period of the wave (2)
What is the function of areolar tissues? (2)
Calculate the number of particles (2)
Why was it necessary to shake the bottle? (2)
What will happen to its density? (2)
What will be left in the flask after heating? (2)
While performing the experiment Archimede’s principle (2)
State the role of epidermis in plants (2)
While observing a section of plant stem, Aditi observed that in certain areas, cells are irregularly thickened at the corners (2)
Can you help him in identifying the cellular component A and B? (2)
What should that student infer technically? Give reason (2)