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    Three phase A.C supply

    the line voltage is the voltage "difference" of two phase voltages... that means one phase voltage should be reversed and added to another phase.. than u'll have 2x230xcos(30) as the line voltage (\approx400).... (check for the attachment, then u'll get a better idea)
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    Break beam IR emitter and detector

    maybe you are right about hall probe sensors... I just had that idea of break beam sensors, because we had a robot competition recently in our university... and we used some break beam sensors plus some other sensors for the robot...our group got the second place... anyway i searched hall probe...
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    What are the 'dict-cache' files?

    yes, im running JDK... ya, maybe that is why those were there at the temporary folder... I thought those files were downloading automatically.. anyway thank you so much... if you know more about these files, please be kind enough to explain it more... thanx..
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    Break beam IR emitter and detector

    hey guys... thank U so much... I was thinking of designing a device for measuring speed and distance of a foot cycle... Now I have nice begining... if you have any suggestions please post....
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    Break beam IR emitter and detector

    I need a list(data numbers) of short range IR emitter and detector(not very expensive) which can be used as a break beam sensor.. I also like to know what is the specific IC number which is used to tune the IR emitter's frequency which matches with the detectors receiving frequency. I have heard...
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    What are the 'dict-cache' files?

    when I'm using internet by my USB modem , I saw that lot of files downloaded automatically.. At that time all the automatic updatings (Windows, Antivirus) were OFF. I'm paying my internet bill depending on the capacity I download and upload... so this unidentified files were real problem to...
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    Concave & convex bridges

    I want to know when a vehicle travels at a constant velocity along a convex and concave bridges, in what bridge the normal reaction of the vehicle is higher... I think it is on cancave bridge... am I right? because I got it by equations...
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    Internal forces on a system of particles

    it is just a matter of what is your system...you have the total freedom to choose your system..if your system is a one particle , then you will have to take the internal forces only on it.. if the system is lot of particles then it is something like you are pushing your own hands against each...
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    Does making ice take energy?

    hey Im not very much friendly with these thermodynamics.. but I have studied it in my 1st year.. (but now Im in electronic department..!).. anyway I remember the 'entropy' was something which make lot of us crazy and crazy :-)... whatever it is I have a comment on this ... yes of...
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    Electromotive force

    as i have learnt , electromotive force is the the energy requires to drive +1 charge(unit charge) along the path.. say you have a circuit which describes as a closed path with 'no' any resistance... then you dont have any disturbance to drive any charge along that path..that means the required...
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    Maintaining constant Potential Energy

    I think it is not good to mix up the energy and the force.. say that you are lifting a stone against the gravity.. then as you and I have heard we can use E=Fx to find the energy.. but here it has assumed that the lifting process has done in uniform velocity.. that is why E=Fx and not E=Fx + 1/2...
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    I don't quite get Newton's third law

    the third law confusion.. well .. it can be explained like this... the force and the reaction which describe in the third law are acting on different objects.. one force act on the box and the other act on the the hand.. both are same and opposite in direction.. if you take the box alone only...
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    Voltage divider biasing

    hey... urekaaaa.... I think i got it... there is a wonderful equation.. gm=Ic / Vt, here gm is the transconductance, Ic is the DC bias collector current, Vt is a constant voltage about 26 mA at 300 kelvin.. together with that equation we can use this one too, ro=(Vce + Va)/ Ic, ro is parallel...
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    Voltage divider biasing

    Thank you friends... every advise & opinion you gave to me were really helpful.. I think i have to start solving the problem again with a different start... thank you a lot... but still if you people have something important regarding this matter it will be really really helpful to me & others...
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    Voltage divider biasing

    well i will tell my problem with detail.. it is a common emmiter amplifier with voltage divider biasing, included all the three capacitors(input, output and to short circuit the emmiter terminal(paralell with emmiter resistor)).. given datas are - supply=12v , beta-100, base emmiter...
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    Voltage divider biasing

    I read the Wikipedia.. it says that the ratio should be selected as the way the operating point of the transistor is independent of β.. in our practical of biasing BJT in university we were given that the ratio as '3' or something like that..(constant value). my problem is , 'is that a...
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    Voltage divider biasing

    I want to know is there any constant or suitable ratio for external two resistors which we use for the base of the BJT in 'voltage divider biasing'? I have heard that the ratio of those two resistors should be something like 3.. but im not sure...
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