What do we get from cereals, pulses, fruits and vegetables?
i. From cereals like wheat, rice, maize, we get carbohydrates which provide energy.
ii. Pulses like pea, gram, soybean give us proteins.
iii. Fruits and vegetables are a rich source of vitamins and minerals. A small amount of proteins, carbohydrates, and fats are also present in them.
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?
What is genetic manipulation? How is it useful in agricultural practices?
How are fish obtained?
What are the desirable agronomic characteristics for crop improvements?
Which method is commonly used for improving cattle breeds and why?
What factors may be responsible for losses of grains during storage?
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?
What are the major divisions in the Plantae? What is the basis for these divisions?
Certain force acting on a 20 kg mass changes its velocity from 5 m s-1 to 2 m s-1. Calculate the work done by the force.
Which organelle is known as the powerhouse of the cell? Why?
Composition of the nuclei of two atomic species X and Y are given as under
X Y
Protons = 6 6
Neutrons = 6 8
Give the mass numbers of X and Y. What is the relation between the two species?
What is the physical state of water at—
(a) 25°C (b) 0°C (c) 100°C ?
How does the sound produced by a vibrating object in a medium reach your ear?
A driver of a car travelling at 52 km h-1 applies the brakes and accelerates uniformly in the opposite direction. The car stops in 5 s. Another driver going at 3 km h-1 in another car applies his brakes slowly and stops in 10 s. On the same graph paper, plot the speed versus time graphs for the two cars. Which of the two cars travelled farther after the brakes were applied?
Do you know of any activity which may be polluting this water source?
What are the limitations of J.J. Thomson’s model of the atom?
Can there be displacement of an object in the absence of any force acting on it? Think. Discuss this question with your friends and teacher.