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    Definite Integration proof

    Hey guys! I'm looking for a rigorous proof which shows that the definite integral does indeed give us the area under a curve or which proves how is a definite integral a summation process. I already know that the any given function is the derivative of the function of its area but most of the...
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    Can I do masters in aeronautics after BMechE?

    I am in my first year of ME. I want to know If I can do masters in aeronautics after my Bachelors? Any help will be greatly appreciated. Regards, Abdullah
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    Second Order DE

    since m=+/-2 y is of the form y=A(e^-2x)+B(e^2x) y`=-2A(e^-2x)+2B(e^2x) Use the given conditions. Make two equations... You know the rest. Hope this helps. Abdullah Whats wrong with the forums? It won't allow me to start a new thread. It keeps saying: The page your looking for can't be found...
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    Hybridization of compounds

    I read somewhere on net that hybridization, which is a good model for most of the compounds, is not entirely correct i.e. some molecules show considerable deviation in there molecular geometry from the predictions of the hybrid model and we only use it because it is easier way to understand the...
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    Momentum question.

    Oh my mistake. It is v=-eu. Original post edited. I asked this question because nowadays we are doing oblique collisions between a wall and a ball in mathematics. This is an example question(it appeared in exams a few years ago). Velocity of the ball=u angle which the ball makes with the...
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    Momentum question.

    Guys I'm having a little problem in undersatnding a few things: We have a wall and a ball of mass 'm'. The ball is thrown towards the wall with speed u and rebounds with speed 'v'. The coefficient of restitution is, e is 1/3. The question is to find the value of 'v'. Thats how I think it should...
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    Schools Advice on Universities in Canada for international students.

    I’m a student of A’ Level with Phys, Chem., Math, Further Math and General Paper English as my subjects. I just wanted to know which Canadian universities are not only good for their mechanical/electrical engineering programmes but are also affordable for international students (low tuition...
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    A question about dy/dx

    I'm just a little confused about dy/dx. I read that its one entity not a fraction. Can someone please clarify why is this not a fraction? According to what I know (delta y)/(delta x) becomes equal to dy/dx as (delta x) appraches zero. If delta x apparaches to zero then delta y should alway have...
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    Two Questions

    No I dont. In my opinion the KE of the ball will be used to open the valve...
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    Two Questions

    A system is developed as shown in the diagram attached. The ball is initially given a push so that it falls onto a turbine connected to generator which produces electricity. After rotating the turbine the ball fall down a narrow tube with a valve into the water again the ball rises again and is...
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    Nuclear waste.

    I was just reading about transmutation. From what I have read, it seems like a very good way to deal with the long-lived radioactive waste. I've also read that during this process energy is released which can be used to produce electricity. If that's true why not US or other countries...
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    Nuclear waste.

    Can the nuclear waste from nuclear reactors be used to make nuclear weapons? Secondly, Whats wrong in burying nuclear waste deep inside the Earth or beneath the oceans? And lastly, are the hazards of nuclear waste from nuclear reactors exaggerated? Any help will be appriciated.:smile:
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    I^2=1? How can this be?

    i^2=1? How can this be? First all I must tell you people that I have no doubt that i^2=-1 but what am I doing wrong in the following steps? i^2 =i * i =sqrt(-1) * sqrt(-1) =sqrt(-1*-1) =sqrt(1)=1?:confused: I asked my mathematics teacher but he was unable to find any error in it. Thanks...
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    Mathematica Proof by mathematical Induction: Divisibility

    The question is: Prove by mathematical Induction that f(n) \equiv 2^{6n}+3^{2n-2} is divisible by 5. This is what I did: Suppose that the given statement is true for n=k Since the f(k) is divisible by 5, f(k)=5A (where A are is a constant.) Also, from the given statement...
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    Short and simple question

    What exactly is an echelon matrix? I searched the web and did find some useful results but I'm still a little confused. :confused: Thanks in advance for any help. :smile:
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    Hrlp Please

    Some one please make me understand why electrons closer to the nucleus have less energy than the ones which are farther from it. Is it because they have more potential energy? Secondly, How do we know that protons exist as particles but not as a ball of positive charge. Thanks in advance for...
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    Electrolysis of Brine

    Electrolysis of Brine... Why does castner-kellner cell produces Na. I was always told that Na formed too stable an ion to be reduced when it is in aqueous solution even when the solution is concentrated. I myself have carried out this experiment by elecrolysing concentrated aq. Sodium...
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    Tenth planet Thread (merged)

    According to BBC some people want to name this new "planet" Xena (The warrior princess) :yuck: It sounds stupid for a plaanet...
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    Best movie scenes

    Saving Private Ryan: The first 30min are just awesome... BraveHeart: The last few scenes... These two were the best. The "Neo vs Loads of Agents Smiths" scene from Matrix reloaded wasnt bad either.
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    A simple question

    This is an actual question from the past papers. The question is: It is stated that many forms of transport transform chemical energy into Kinetic energy. Explain why a cyclist traveling at content speed is not making this transformation and explain what transformations of energy are taking...
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    Get them across the river

    The servant has now 3 girls :devil:. So he'll definitely run away with them.:biggrin: This brain teaser does have an answer. But I won't reveal it just yet.
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    Get them across the river

    Since the servant has two girls, he'll run away with them. So that's a wrong answer.
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    Get them across the river

    There are six people. They are: A king, A queen, A knight and his wife, A servent and his wife. There is one boat and they all want to cross the river. The problem is: the boat cannot take more than 2 people. Your job is to tell them a way so that they can all get across the river. Rules...
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    A very funny personality test!

    I believe 2 and 3 are for guy2 and guy1 respectively. If that's the case then atleast for me the result is OK, not very good but not very bad either. I must admit that I am narrow-minded and sometimes can feel a lot of jeolousy but 75% is a bit too much. I don't take advantage of others(atleast...
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    A very funny personality test!

    So when are we going to get our result? :tongue2:
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    A very funny personality test!

    hmm... Girl: 15 (she DOES love him) GUY1: 75 Guy2: 0 (he just explioted the girl) Guy3: 10
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    Urgent Question, must know!

    about:blank :(
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    Flemings Left Hand Rule

    Well I think when motion is produced by a current in a conduct, we use Flemings Left Hand rule to predict the direction of motion. Whereas, when motion is producing current we use FLEMINGS RIGHT HAND RULE. It’s same as Flemings Left Hand rule but this time you do it with your right hand to...
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    I need some advice

    LOL I'm just in A'levels so I don't think I will get a chance to do that. :smile:
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    Launch of space shuttle

    It was a successful launch. BTW, Does anyone the maximum speed that the shuttle reached?
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    I need some advice

    First of all, thanks a lot for the replies guys. That is exactly what is happening with me. Moreover, I feel like I don’t know anything that’s why I write/say things repeatedly. I'm going to check the sites which zoobyshoe linked to. I hope they help to solve this problem...
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    I need some advice

    I'm not at all interested in philosophy. In fact, I hate it. :yuck:
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    I need some advice

    Since the last 3 or 4 months I'm having a lot of trouble. I love phys, math and chem. I love them so that even when I go to bed to sleep my mind can’t stop thinking about them. But as I said before since the last 3 months, I can’t understand anything. When my teacher teaches me something I think...
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    Body Hair

    I have the hairiest legs and arms in my family. Even my friends sometimes call me a bear. I also have a small patch of hair right in middle of my chest.
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    Things I Love from America

    Yeah, I've seen the photos. I've even watched a television documentary on it. I just hate the people who say humans didn’t land on moon. They say there are a lot of lighting anomalies which prove that the photos are fake. My brother was with me and I showed him that everything was possible. As...
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    Calculate the forward driving force which accelerates the car down the slope.

    There is a 760N heavy car on a plane which is inclined to the horizontal at an angle of 6.8 degrees. Calculate the forward driving force which accelerates the car down the slope. I know the answer is 760sin6.8. I know that the forward driving force has a direction which is parallel to the...
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    Another fun survey

    Economic Left/Right: -1.00 Social Libertarian/Authoritarian: 0.87
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    Exam question

    Well yesterday it was my physics paper(o'levels) . There was a question there which asked what is the advantage of having cells connected in parallel combination? I wrote that By connecting the cells in parallel combination the total current in the circut is shared by all of the cells as a...
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    Astable and bistable

    Astable and bistable have been recently added in our syllabus. As a result it’s not in my textbook. My teacher did give a lecture on it but unfortunately I didn’t get a single thing... Can you guys please give a link to some site(s) which give(s) a good introduction to the Astable and bistable...
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    Find the remainder when 1/f(x) is divided by x+1

    It is given that f(x)=8x^3+4x-3. The question is: Find the remainder when 1/f(x) is divided by x+1. My textbook says the remainder does not exist? I just can't solve it. Thanks in advance for any help. Abdullah
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    E-4 Mensuration Question

    Damn I was wrong. You can definitely add the sixth level which makes the no. of max spheres 543. I was making a simple error.
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    E-4 Mensuration Question

    I worked on it and found out that maximum no. of spheres in only possible if they are placed directly on to each other. For this particular problem if the spheres are placed as you have said than there are two possibilities. Either the no. of spheres that can be packed is (81+100+81+100+81)=443...
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    E-4 Mensuration Question

    Well along the width of the base 10 spheres can fit same is the with the length of the base. Along the height of the box 5 sphere can fit. So the total no. of spheres is 10x10x5=500 spheres. That's what I think.
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    News Cartoon in washington post.

    That's stupid. I still think it was intentional. I still remember seeing an American cartoon in which the term DOG was used as an abuse. Even in english language the expressions with dog in them always have negative meanings. And after all this he was thinking that personifying Pakistan as a dog...
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    News Cartoon in washington post.

    I'm sorry about writing washington post instead of times. I feel like a complete idiot.
  46. D

    Frequency of collisions of the gas

    Now I get it. Thanks a lot whozum. :approve:
  47. D

    Frequency of collisions of the gas

    Thanks a lot for your replies whozum. But I really don't think I'm getting you. Can you please provide some explanation. I shall be very thankful to you if do so. :) I personnaly think that the freqency of collisions will be reduced. My teacher says it won't be reduced infact it will remain the...
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    Frequency of collisions of the gas

    They are directly proportional. I know that the pressure will increase but since the piston is friction less it will move outwards until the pressure inside the syringe is same as it is outside the syringe. But that's not my question.
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    Frequency of collisions of the gas

    Some gas is put into a gas syringe with a frictionless piston which does not allow the escape of any gas. The gas is initially at 20C and is then heated to 100C. The piston is allowed to move. At 100C a time will come when the piston will stop moving outwards and become stationary(this will...
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    News Cartoon in washington post.

    I was going to say the same thing. US government financially helped the Taliban to defeat the Soviet Union. And So-crates Pakistan is not a military dictatorship. Most the literate people here support Musharaf and want to see him in both the uniform and as the president of Pakistan. Cross-border...
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