English Medium Class 9 - CBSE Question Bank Solutions for Science

During summer, if you go near the lake, you feel relief from the heat, why?

Weeds affect the crop plants by

Berseem is an important ______ crop.

______ are rich in vitamins.

______ crop grows in winter season.

What is a GM crop? Name anyone such crop which is grown in India.

Kharif crops are cultivated from ______ to ______.

Discuss the role of hybridisation in crop improvement.

Figure15.1 shows the two crop fields [Plots A and B] have been treated by manures and chemical fertilizers respectively, keeping other environmental factors the same. Observe the graph and answer the following questions.

(i) Why does plot B show a sudden increase and then a gradual decrease in yield?

(ii) Why is the highest peak in plot A graph slightly delayed?

(ii) What is the reason for the different patterns of the two graphs?

Liquids generally have lower density as compared to solids. But you must have observed that ice floats on water. Find out why.

Which postulate of Dalton’s atomic theory can explain the law of definite proportions?

When 3.0 g of carbon is burnt in 8.00 g oxygen, 11.00 g of carbon dioxide is produced. What mass of carbon dioxide will be formed when 3.00 g of carbon is burnt in 50.00 g of oxygen? Which law of chemical combinations will govern your answer?

Where is apical meristem found?

Does the transfer of energy take place when you push a huge rock with all your might and fail to move it? Where is the energy you spend going?

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

How does the atmosphere act as a blanket?

How are clouds formed?

You have seen weather reports on television and in newspapers. How do you think we are able to predict the weather?

What are macro-nutrients and why are they called macronutrients?

How do plants get nutrients?