Getting energy from water. Read this in a book
In water, H2O, some times we may find a heavier isotope of Hydrogen, called Deuterium. (Atomic mass of normal Hydrogen atom = 1, of Deuterium = 2). It has been known for long that two Deuterium atoms can be fused to form an atom of Helium. Thats what happens in the sun and other stars. 1kg of Deuterium provides as much energy as 14 million kgs of coal burned. And, our oceans have enough Dueterium as part of water to last mankind for 30 million years (if mankind survives that long).
However, to fuse two deuterium atoms, we need a temperature of 200 million degree Celsius. At this high temperature, everything converts into plasma, even the installation in which such a conversion is attempted. Hence, it isnt viable to store plasma in a container, and hence it is packed using magnetic fields. However, plasma always seeks a crack in the magnetic fields, and finding one, breaks free and the deuterium flies off in all directions and is lost.
Soviet scientists had designed and built a series of installations called TOKAMAK to provide high temperatures. However, the maximum they can go upto is 20 million degrees, just 10% of what we require.
Hence, scientists have found another way. They take a small granule of ice of water having deuterium. A laser beam is directed at it. This heats it to a very high temperature. But before it melts to form water, the deuterium atoms in it start fusing and realease energy. This causes an explosion, which realeases the energy, though in very small quatities. In order to get a sizable amount of energy, 20 granules of ice should be exploded per second.
This energy is used to heat liquid lithium, which transmits heat to water (normal). The water turns to steam and is directed to a turbine which generates electricity.
The use of this method, (called thermonuclear energy) not only produces a great deal of energy, but is also non-polluting.
Hydrgen is a highly combustible fuel. Also, using hydrogen is economically viable, as huge quantities of it are present in the seas and in crude oil. Also, hydrogen burns to form water, and hence hydrogen is the cleanest fuel. At present, hydrogen is extracted from crude oil, which is an expensive process, and produces very little H2. So instead, electrolysis can be used to extract H2 from the seas. However, this would require a lot of electricity itself, which can only be provided by a nuclear power station.
So, scientists have come up with a design of a floating nuclear power station on the seas and oceans. All electricity produced would be used to extract hydrogen, which would be pumped to the mainland through pipelines. This H2 would then be converted to liquid before being distributed to the final consumers. It may give two benefits. Burning liquid hydrogen will give power, and also forms water, the purest water on earth. So, both power and water needs of people are satisfied.
However, proper storage of hydrogen gas is necessary, since, if kept in the open, it will evaporate, and if tightly shut, it may craete pressure and explode. So, the containers must be open only just enough to avoid an explosion, and yet retain as much hydrogen as possible.
The solution to Q 17 is absolute BS......laughable. For all my money my score should be 60.67 and not 59.33, would have been very comforting to have a 60+ score.
Sectional scores and Appr %iles :-
VA/RC --> 27.33 %ile = 99.3
QA --> 10.33 %ile = 94
DI --> 21.67 %ile = 92.5
Overall --> 59.33 with %ile = 99.4 and AIR 66. Feels good to have a good %ile after many "not so inspiring" performances in the TIME mocks. I really needed a confidence booster and this mock has been just that. I am pretty pleased that in VA/RC I am finally where I belong, 99.3+ which should give me some hope to get past 99.5 in CAT.
Somehow I dont yet figure in the Toppers List inspite of clearing all cutoffs but then I havent seen even a single guy from Blore in the Toppers list. Maybe they havent yet updated the Toppers List with the Blore results.......as per the current list I should be looking at a rank of around 30-35.
ATB for the next one.
Edit: I Can now see my name at the 49th place in the Toppers List.:)
For the I question : It was given that A is a number such a way that A+2 is exactly divisible by 15,16,17,18 and 19. Hence A is lcm of 15,16,17,18 and 19 -- 2. Which comes out to be 15504 -- 2 = 15502 = 2 * 7751. Now B is product of 15, 16, 17, 18 and 19. HCF for the 2 numbers is 2. Hence 2 is the answer
i guess we are sailing the same boat.my scores are an almost replica of ures(xcept for QA where uve scored heavily).my neta ttempts being the same as you,ie 58 and my relative scores are:
but wen i saw ppl scoring in 60's and dat tooo very easily..i was really taken aback. didnt turn out a good week for me either.feeling slitely low after that.
but i guess everyone passes thru dat phase once a while in CAT preparation. i have been getting percentiles ranging frm 97-99 in all FLT's and MOCKS but somehow screwed up the last one.
lets see whats in store for me dis sunday.
all the best!
ps: wat ru doing to improve da no of attempts? mine just dnt cross 70-75
A much needed wake-up call........
Ended up at overall score = 42.00 and %ile of 88.5. Didnt clear even a single cutoff, not even VA/RC, just abt managed to hit 90%ile here.........
The cutoffs here are definitely on the higher side compared to TIME and do appear more realistic, good that I got a sound beating in my first CL mock. All the junta has happily cracked 20+ in DI and I was kinda pleased with a score of 17 which was brought down to 15 because of the key changes. Net result :- 70%ile in DI
Lots of catching up to do.......its been a bad week, screwed up both TIME and CL mocks.
ATB for the next one.
2.A school boy starts at a particular time from his house.After travelling fro 1/3 rd of the distance he is at the railway station at 7:25 and after travelling 3/4 th of the remainging distance he is at some other place at 7:30.Now at what time did he start from his house and at what time will he reach his school?
Pleasee solve these questions:
4.A train blows a siren one hour after starting from the station. After that it travels at 3/5th of its speed it reaches the next station 2 hours behind schedule. If it had a problem 50 miles farther from the previous case,it would have reached 40 minutes sooner. Find the distance between the two stations .
5.Mr. ANYMAN left ANYTOWN by car to attend a wedding at ANYCITY. He had been driving for exactly two hours when the car got punctured. It took his driver exactly ten minutes to change the wheel. In order to play safe they covered the remaining distance at a speed of 30 mph. consequently, Mr. ANYMAN was at wedding half an-hour behind schedule. Had the car got the puncture only 30 miles later , I would have been only FIFTEEN minutes late he told the driver . How Far is ANYCITY from ANYTOWN.
A school boy starts at a particular time from his house.After
travelling fro 1/3 rd of the distance he is at the railway station at
7:25 and after travelling 3/4 th of the remainging distance he is at
some other place at 7:30.Now at what time did he start from his house
and at what time will he reach his school?