Recent content by lmlgrey

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    Just finished with my 4-year B.Sc. program now thinking engineering

    and there really isn't anything particularly exciting about it! im not sure where im going next year despite the fact that i got accepted into some master programs...madly expensive and no job demands. they're mostly masters program in publich health. one of them is at Columbia - was pumped at...
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    Some hints on the question please? thanks!

    some hints on the question... please?!! thanks! 1. Assume that the region to the right of a certain vertical plane contains a vertical magnetic field of magnitude 1.00 mT, and the field is zero in the region to the left of the plane. An electron, originally traveling perpendicular to the...
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    I don't know where went wrong help needed!

    1. Two parallel conducting plates that are in deep space are brought to a potential difference of 4.50E+3 V, and a small pellet of mass 5.70 mg carrying a charge of 7.75*10^-7C accelerates from rest from the positive plate. With what speed will it reach the other plate? It...
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    Why is it possible

    A reaction happened between HCl and antacid (which contains calcium carbonate) and the reaction flask was equipped with a pressure detector... by calculating the difference between # of moles of gas in the flask before and after(nf-ni=(pf'/Tf-pi'/Ti)*V/R...
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    Why is it possible

    1. When determining the concentration of calcium carbonate in an antacid tablet, why using a wet flask will end up with a significant higher concentration???? 2. Gas laws I would expect a lower yeild of gas since some of the calcium carbonate reacts with water and escape from the...
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    Very Simple exponential growth problem

    ok... It seems that i completely forgot the contant part :P now I integrated the function and got: D(x)= sqrt(0.2x^4+8000)+C D(0)= sqrt(8000)+C 500= sqrt(8000)+C C= 410.557 Then D(10) = sqrt(0.2*10^4+8000)+410.557= 510.557 acre ---- does it look right? ...also, if I do what Hallsofivy...
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    Very Simple exponential growth problem

    1. It is estimated that x years from now the value of an acre of farmland will be increasing at the rate of \frac{0.4x^3}{sqrt(0.2x^4+8000)} dollars per year. If the land is worth 500 per acre, how much will it be worth in 10 years? 2. Use integral Since the the function of money...
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    Use integration to find the total force on a point HELP!

    oh, i see... so now since only the x-component is considered then cos theta = D/r and the function becomes: dF=(kqQ/2Lr^2)dy * D/ r ... is that correct??? then further integrating the above gives: F= k*q*Q*D^2/2L* ∫1/(D^2+y^2)^-2/3 8 dy??? -- did i do this step correct??
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    Use integration to find the total force on a point HELP!

    http://capa.mcgill.ca/res/mcgill/dcmcgill/oldproblems/newerlib/Graphics/Gtype51/prob19a.gif[/URL] 1. A charge Q = 8.10 ×10-4 C is distributed uniformly along a rod of length 2L, extending from y = -11.4 cm to y = +11.4 cm, as shown in the diagram 'on your assignment above. A charge q = 1.80...
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    Simple pendulum question help needed

    Simple pendulum question.. help needed!!!! http://capa.mcgill.ca/res/mcgill/dcmcgill/oldproblems/msuphysislib/Graphics/Gtype26/prob34a_pendSHM1.gif1.[/URL] The diagram shows a simple pendulum consisting of a mass M suspended by a thin string. The magnitude of the tension is T. The mass swings...
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    Confused about force/impulse/acceleration

    The question goes 1. Recent studies have raised concern about `heading' in youth soccer (i.e., hitting the ball with the head). A soccer player `heads' a size 5 ball, deflecting it by 58.0 deg, but keeping its speed of 15.80 m/s constant. A size 5 ball has a mass of approximately 0.426 kg...
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    A question on double-pulley

    1. For the modified Atwood machine of this problem, assume that the two masses do move. Also assume that there is no friction, and that gravity is the only force acting. Also assume that you can ignore the mass of the pulleys and of the connecting rod and string. Notice that mass m1 is rigidly...
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    Simple tension situation help needed

    Okkk. I see! I can interpret it as it is a massless rope, but there is each an object that attaches at A,B,O,P which weighs the same...... ok, now I get it. The acceleration would be the same since the the whole system has only one acceleration but tension force is different since there are...
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    Simple tension situation help needed

    I noticed that its a heavy rope... but I dont understand the difference it makes.. so the tension force is not constant throughout the rope?\ and yes, A,B,O,P are points on the rope therefore, connected.
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