Class 9 Science - Chapter Improvement in Food Resources NCERT Solutions | Compare the use of manure and fertilizer

How do you differentiate between capture fishing, mariculture and aquaculture?

Explain any one method of crop production which ensures high yield.

How do good animal husbandry practices benefit farmers?

What are the desirable characters of bee varieties suitable for honey production?

How do plants get nutrients?

How are fish obtained?

What is genetic manipulation? How is it useful in agricultural practices?

What are the desirable agronomic characteristics for crop improvements?

What factors may be responsible for losses of grains during storage?

Which method is commonly used for improving cattle breeds and why?

Which of the following has more inertia: (a) a rubber ball and a stone of the same size? (b) a bicycle and a train? (c) a five-rupees coin and a one-rupee coin?

State the universal law of gravitation.

Which of the following are matter?

Chair, air, love, smell, hate, almonds, thought, cold, cold-drink, smell of perfume.

A force of 7 N acts on an object. The displacement is, say 8 m, in the direction of the force (Fig. 11.3). Let us take it that the force acts on the object through the displacement. What is the work done in this case?

What is meant by a pure substance?

How does the sound produced by a vibrating object in a medium reach your ear?

In a reaction, 5.3 g of sodium carbonate reacted with 6 g of ethanoic acid. The products were 2.2 g of carbon dioxide, 0.9 g water and 8.2 g of sodium observations are in agreement with the law of conservation of mass.

sodium carbonate + ethanoic acid → sodium ethanoate + carbon dioxide + water

What are canal rays?

State any two conditions essential for good health.

How is our atmosphere different from the atmospheres on Venus and Mars?

The average atomic mass of a sample of an element X is 16.2 u. What are the percentages of isotopes ¹⁶₈ X and ¹⁸₈ X in the sample?

Diagrammatically show the difference between the three types of muscle fibres.

The mass per unit volume of a substance is called density. (density = mass/volume). Arrange the following in order of increasing density – air, exhaust from chimneys, honey, water, chalk, cotton and iron.

Write the steps you would use for making tea. Use the words solution, solvent, solute, dissolve, soluble, insoluble, filtrate and residue.

Helium atom has an atomic mass of 4 u and two protons in its nucleus. How many neutrons does it have?

Define 1 watt of power.

Look at the activities listed below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
  • Suma is swimming in a pond.
  •  A donkey is carrying a load on its back.
  •  A wind-mill is lifting water from a well.
  •  A green plant is carrying out photosynthesis.
  •  An engine is pulling a train.
  •  Food grains are getting dried in the sun.
  •  A sailboat is moving due to wind energy.

An object of mass 40 kg is raised to a height of 5 m above the ground. What is its potential energy? If the object is allowed to fall, find its kinetic energy when it is half-way down.

If the moon attracts the earth, why does the earth not move towards the moon?

If action is always equal to the reaction, explain how a horse can pull a cart.