Find out how much cellulose is made by all the plants in the biosphere and compare it with how much of paper is manufactured by man and hence what is the consumption of plant material by man annually. What a loss of vegetation!

A plant breeder developed a hybrid sugarcane by grafting two differents varieties with desirable characters. The resultant hybrid showed as excellent growth and productivity with increased sucrose contant compared to its parental forms. (i) What does this phenomenon refers to? (ii) How its condition can be maintained through further generation?

The species diversity of plants (22 per cent) is much less than that of animals (72 per cent). What could be the explanations to how animals achieved greater diversification?

The given graph shows how much nitrate (NO_(3)^(-)) is exported from the continent towards the ocean by 16 major rivers in the world rivers in the world compared to the density of human populations living along those drainage basins (i.e., along these rivers). What interpretation can be drawn from this graph ?

A company produces two types of belts A and B. Profits on these types are 2 and 1.5 on each belt respectively. The belt of type A requires twice as much time as a belt of type B. The company can produce utmost 1000 units of belt per day. but the supply of leather is sufficient for 800 belts per day is available, Utmost 400 buckles for belts of type A and 700 for those of type B are available per day. How many of each type of belts should be produced so as to maximise the profit assuming that the company can sell all the items produced. What is the maximum profit?

A particle of mass 1 g and charge 2. 5 xx10^(-4) C is released from rest in an electric field of 1.2 xx 10^4 NC^(-1) (a) Find the electric force and the force of gravity acting on this particle. Can one of these forces be neglected in comparison with the other for approximate analysis? (b) How long will it take for the particle to travel a distance of 40 cm? (c) What will be the speed of the particle after travelling this destance? (d) how much is the work done by electric force on the particle during this period?

A king ordered his Goldsmith to make a crown which should be of pure gold. SO the goldsmith to made a crown of pure gold & brought it to king. but the king was not contended with the crown as he suspected whether it is made of pure gold or not. So he called for Archimedes and asked him to check whether it is a pure gold crowm. Archimedes was serious about this and went his home thinking how to solve this issue. He wanted to take bath, all of a sudden the jumped on to the bath tyb. Water inside the tub had splashed out of it. An idea striked him suddenly he went running naked straight from his bathroom to the king's pace shouting Eureka Eureka on the road side. From this what do we infer ? How Archimeded would have solved this problem ?

A king ordered his Goldsmith to make a crown which should be of pure gold. SO the goldsmith to made a crown of pure gold & brought it to king. but the king was not contended with the crown as he suspected whether it is made of pure gold or not. So he called for Archimedes and asked him to check whether it is a pure gold crowm. Archimedes was serious about this and went his home thinking how to solve this issue. He wanted to take bath, all of a sudden the jumped on to the bath tub. Water inside the tub had splashed out of it. An idea striked him suddenly he went running naked straight from his bathroom to the king's pace shouting Eureka Eureka on the road side. From this what do we infer ? State Archimedes principle.

An object is placed vertically at a distance of 20 cm from a convex lens. If the height of the object is 5 cm and the focal length of the lens is 10 cm, what will be the position, size and nature of the image? How much bigger will the image be as compared to the object?

Kavitha thought of constructing 2 more rooms in her house. She enquired about the labour. She came to know that’s 6 men and 8 women could finish this work in 14 days. But she wishes to complete that work in only 10 days. When she enquired, she was told that 8 men and 12 women could finish the work in 10 days. Find out how much time would be taken to finish the work if one man or one woman worked alone.

A small town with a demand of 800 kW of electric power at 220 V is situated 15 km away from an electric plant generating power at 440 V. The resistance of the two wire line carrying power is 0.5 Omega per km. The town gets power from the line through a 4000-220 V step-down transformer at a sub-station in the town. a. Estimate the line power loss in the form of heat. b. How much power must the plant supply assuming there is negligible power less due to leakage? c. Characterise the step up transformer at the plant.