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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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    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.

    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

    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.

    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...
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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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    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

    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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    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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    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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    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 text book says the remainder does not exist!?! I just cant solve it. Thanks in advance for any help. Abdullah
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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.

    Few days ago the Washington post in America printed a cartoon in their newspaper. It had a DOG with Pakistan written over it and an American soldier standing close to it. I thought alot about it and really pissed me off. What do they really want? They hate us when we dont support them in their...
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    Estimation of Square roots

    How can I estimate the value of sqrt. of a particular no. which is not a perfect square(e.g. 125) without using the calculator? Secondly how does the Calculator solve it? Does it use logrithms? If it does how does it solve them?
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    Mind power and black magic

    Do you people believe in them? Do they have any scientific bases? As for me, I myself think that they are nothing but non-sense.
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    I've been bitten by a dog

    I've been bitten by a dog!!! Today, about 5 hours ago, when we (I and my two friends) were on our way home from my tuition, a pet dog came running towards us. Initially, we all thought that since it was pet dog it wouldn’t bite us so we didn’t change our course but just after few seconds we...
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    A question about SR

    I was reading about special relativity on How Stuff Works. In the article, the writer has given the following 4 points: 1. Energy must be added to the system to increase the ship's speed. 2. More of the added energy goes towards increasing the system's resistance to acceleration. 3. Less...
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    Persistence of vision

    I know it is used to refer to the property of brain/eye that it takes them one-tenth of a second to process a new image after processing one but I just cant figure out how does a movie camera takes advantage of it and fool our brain so that it thinks that its waching a smooth motion though i...
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    A snooker ball

    In snooker, I've noticed many times that it you hit some ball in right place the white ball will stop at the point of contact but the ball that was hit starts moving. Is this true that the white ball tranfers all of its momentum to the other ball and since there is no more momentum left it stops?
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    What is relative velocity?

    What is relative velocity? I have solved alot of questions relating to it but I'm still confused what EXACTLY is it? Its in my maths book so my mathematics teacher was not able describe this in detail. One more thing: I'll be much pleased if someone also explains what is relative path. Thanks...
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    My brother

    My elder brother has decided to study abroad for heigher studies. He's a bit reluctant though. This is because here we have heard loads of stories about people in America and europe hating us specially after 9/11. Is it true?
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