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?
How do good animal husbandry practices benefit farmers?
Explain any one method of crop production which ensures high yield.
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?
You find your mass to be 42 kg on a weighing machine. Is your mass more or less than 42 kg?
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?
If Z = 3, what would be the valency of the element? Also, name the element.
Give reasons for the following observation:
The smell of hot sizzling food reaches you several metres away, but to get the smell from cold food you have to go close.
Explain with examples (i) Atomic number, (ii) Mass number, (iii) Isotopes and iv) Isobars. Give any two uses of isotopes.
State the universal law of gravitation.
Why will a sheet of paper fall slower than one that is crumpled into a ball?
What is the greenhouse effect?
Calculate the number of aluminium ions present in 0.051 g of aluminium oxide.
(Hint: The mass of an ion is the same as that of an atom of the same element. Atomic mass of Al = 27 u)
How much momentum will a dumb-bell of mass 10 kg transfer to the floor if it falls from a height of 80 cm? Take its downward acceleration to be 10 m s-2.