Recent content by ank160

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    Time taken by gas to fill empty vessel

    Suppoese there is a empty vessel connected to a pipeline having a continuous supply of gas at pressure P. Gas will continue to move in vessel till pressure in it become P. How to calculate time required to fill the vessel completely. Plz help.
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    Relation b/w elctrical resistance and stress-strain

    Thanks for the explanation.
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    Relation b/w elctrical resistance and stress-strain

    Hey All! My question is regrading a subtle observation that i made when i was straing at my "spring coil type" room heater. Accidently i pulled up some stands of heating coil spring to make them straight section (obviuosly when it was switched off). Then, when i passed current through it...
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    Air brake over hydraulic brakes

    Air brake over hydraulic brakes! Why air brakes are used in long vehicles like trains, instead of hydraulic brakes?
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    Higher efficiency - 2 stroke or 4 stroke diesel engine?

    Hi evry1! Just wanted to know that which has got higher efficiency - 2 stroke diesel engine or 4 stroke diesel engine. I believe that direct injection of fuel in diesel engines prevents the loss of unburnt fuel in exhust of 2S engine. And simpler mechanism and lesser no. of moving parts in 2S...
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    What is the role of rotation in mechanics?

    i guess ur basic r not clear that how to work wid non inertial frames when Newtons laws are applied in it...newayys...just see... B is a non-inertial frame having accleration a = v^2/r, in direction from B to A radially. Now if u want to work 4m this frame then u will have to apply a force of...
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    What is the role of rotation in mechanics?

    B would also see A rotating around B.
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    Force on a plate due to air jet

    Suppose there is a plate with area A, on which jet of air with velocity 'v' is striking, then force on it will be = (density) * A* v^2 But if we go by basics i.e. F = d(mv)/dt = v d(m)/dt + m d(v)/ dt here i am not able to figure out that why the second term i.e. m d(v)/ dt is zero...
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    Governing in case of Wind mill

    I want to know that how is govering is executed in case of wind mill to ensure that generator's shaft rotates at constant speed so as to generate electricity at fixed frequncy. Like in case of hydroturbine, governing is done by regulating water flowrate.
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    The reason behind the inverse proportionality r^2 to the force of attraction

    But how did Kepler derived that T^2 is proportional to r^3.
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    Is magnetic field a frame dependent quantity?

    A moving charge constitutes current, which in turn produce magnetic field around it. So does that mean if the observer is also moving with charge, then it will not experience ne magnetic field? And if the same observer is carrying a permanent magnet, then it will not show ne motion to align...
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    Rolling Motion on Rough Surfaces

    Once the body starts rolling then velocity at point of contact become zero. Hence there is no relative motion between body and surface at that point and hence no friction.
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    Entropy change in free expansion.

    The very basic defination of entropy says "its a dergree of randomness" and this the physical concept of entropy. Now if a system containing gas is provided with some external energy then its molecules will start moving rapidly and it will have greater randomness and thus higher entropy. Here...
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    Entropy change in free expansion.

    Well Mr. Andrew Mason thanks 4 ur suggestion, I am surely going to study more abt entropy. But i know how to spell entropy... its- E N T R O P Y , right? :) another thing i want to mention that entropy is not a mathematical quantity , it is a THERMODYNAMIC quantity just like temperature...
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