English Medium Class 9 - CBSE Question Bank Solutions for Science

Write true (T) or false (F)

Blue green algae belongs to the kingdom Protista.

Write true (T) or false (F)

All prokaryotes are classified under Monera.

Prokaryotes are grouped in Kingdom ______.

Give examples for the following

Bilateral, dorsiventral symmetry is found in ______.

A body is thrown vertically upward with velocity u, the greatest height h to which it will rise is,

Area under a v – t graph represents a physical quantity which has the unit

Name the process associated with the following

A drop of ink placed on the surface of water contained in a glass spreads throughout the water.

What are the favourable qualities given to gold when it is alloyed with copper or silver for the purpose of making ornaments?

Give an example of each mixture having the following characteristics. Suggest a suitable method to separate the components of this mixture

Two immiscible liquids.

When light is passed through water containing a few drops of milk, it shows a bluish tinge. This is due to the ______ of light by milk and the phenomenon is called ______. This indicates that milk is a ______ solution.

Non-metals are usually poor conductors of heat and electricity. They are non-lustrous, non-sonorous, non-malleable and are coloured.

Name a lustrous non-metal.

A child wanted to separate the mixture of dyes constituting a sample of ink. He marked a line by the ink on the filter paper and placed the filter paper in a glass containing water as shown in Fig.2.3. The filter paper was removed when the water moved near the top of the filter paper.

(i) What would you expect to see, if the ink contains three different coloured components?

(ii) Name the technique used by the child.

(iii) Suggest one more application of this technique.

Calculate the mass of sodium sulphate required to prepare its 20% (mass percent) solution in 100g of water?

How will the equations of motion for an object moving with a uniform velocity change?

A girl walks along a straight path to drop a letter in the letterbox and comes back to her initial position. Her displacement–time graph is shown in Fig.8.4. Plot a velocity-time graph for the same.

The velocity-time graph (Fig. 8.5) shows the motion of a cyclist. Find (i) its acceleration (ii) its velocity and (iii) the distance covered by the cyclist in 15 seconds.

Draw a velocity versus time graph of a stone thrown vertically upwards and then coming downwards after attaining the maximum height.

An object starting from rest travels 20 m in the first 2 s and 160 m in the next 4 s. What will be the velocity after 7 s from the start?

An electron moving with a velocity of 5 × 104 ms⁻¹ enters into a uniform electric field and acquires a uniform acceleration of 104 ms^–2 in the direction of its initial motion.

(i) Calculate the time in which the electron would acquire a velocity double of its initial velocity.

(ii) How much distance the electron would cover at this time?

Two stones are thrown vertically upwards simultaneously with their initial velocities u₁ and u₂ respectively. Prove that the heights reached by them would be in the ratio of `"u"_1^2 : "u"_2^2` (Assume upward acceleration is –g and downward acceleration to be +g)