mak10

According to Merriam-Webster, its derived from the Greek word hormOn, present participle of horman to stir up, from hormE impulse, assault; akin to Greek ornynai to rouse. -mak10

how is that an imperfection?? I asked my biology teacher about this since this intrigued me and she's like its more of a necessity since warm-blooded vertebrates like us require some very good amount of oxygen to keep the photoreceptors functioning.... and the only way to accomplish this, without compensating on the very important functions of the retinal epithelium, would be the inverted eye arrangement. Although I have trouble understanding the detailed mechanism, in the context of natural selection, had the inverted arrangement possessed an imperfection (and thus a disadvantage),then, why, pray tell, would it have evolved from the non-inverted arrangement (since basically, we know that vertebrates evolved from invertebrates, which possess this non-inverted eye, right?), in the first place?? -mak10

how is that an imperfection?? I asked my biology teacher about this since this intrigued me and she's like its more of a necessity since warm-blooded vertebrates like us require some very good amount of oxygen to keep the photoreceptors functioning.... and the only way to accomplish this, without compensating on the very important functions of the retinal epithelium, would be the inverted eye arrangement. Although I have trouble understanding the detailed mechanism, in the context of natural selection, had the inverted arrangement possessed an imperfection (and thus a disadvantage),then, why, pray tell, would it have evolved from the non-inverted arrangement (since basically, we know that vertebrates evolved from invertebrates, which possess this non-inverted eye, right?), in the first place?? -mak10

the strength of electronegativity depends on the atomic/ionic radii of elements that form molecules with an uneven distribution of charge (polarity). so the strength, in actuality, depends on how close the electrons in a molecule are to the nucleus (which contains the +vely charged protons), not how many protons there are in a nucleus... since the latter may cause (as it does, down a group in the periodic table) a consequent increase the number of the inner shielding electrons that screen the outermost the electron that the element uses for bonding with other elements to form molecules... hence nullifying the effect of more protons. -mak10

the strength of electronegativity depends on the atomic/ionic radii of elements that form molecules with an uneven distribution of charge (polarity). so the strength, in actuality, depends on how close the electrons in a molecule are to the nucleus (which contains the +vely charged protons), not how many protons there are in a nucleus... since the latter may cause (as it does, down a group in the periodic table) a consequent increase the number of the inner shielding electrons that screen the outermost the electron that the element uses for bonding with other elements to form molecules... hence nullifying the effect of more protons. -mak10

wooohoo... thnx a lot swansont! you're a lifesaver! i get the correct answer now.!! -mak10

wooohoo... thnx a lot swansont! you're a lifesaver! i get the correct answer now.!! -mak10

A boy can walk up a stationary escalator in 90s. Standing on the escalator when it is moving, the student goes up in 60s. How long would it take the student to walk up the moving escalator? the problem sounds easy, but its not.... atleast not for me. so any help in solving would be greatly appreciated. thanks! -mak10

A boy can walk up a stationary escalator in 90s. Standing on the escalator when it is moving, the student goes up in 60s. How long would it take the student to walk up the moving escalator? the problem sounds easy, but its not.... atleast not for me. so any help in solving would be greatly appreciated. thanks! -mak10

ingenious... thanks a lot jdurg! -mak10

i still dont get it. whats the new volume? how did you get it? your answer is correct.... it is 4/3 kPa... but can you show me, briefly, the exact steps you took to get this answer? am confused... thanks jdurg! -mak10

partial pressures added gives 3 kPa... but the correct answer is different. -mak10

flask X contains 1 dm3 of helium at 2 kPa pressure and flask Y contains 2 dm3 of neon at 1 kPa pressure. if the flasks are connected at constant temperature, what is the final pressure? any ideas on how to solve this?? -mak10

I don't rememder the details but I do remember two scientists figuring out the cause of aging... some 'kiss of death' property of certain protease enzymes that break down other cells in the process and cause what we call as aging. they say the process can be inhibited and stuff. and i think they were chosen for the Nobel Prize this year for their research... cool, eh? -mak10

i think its more like F = Gm1m2/r^2 where G = 6.67^-11 -mak10

ofcourse! i stand corrected! apologies for all the unwanted confusion! -mak10

ok, maybe I mindunderstood since most of the intelligent people on board here disagree with me.... how i understand this is very simple, a ball is thrown off from a train at 70 mph opposite to the direction of the train which is also travelling at 70 mph, with respect to the ground. both their velocity vectors would cancel off, so they have a zero resultant velocity (as YT said +71-70 = 0). but i dont understand how this affects the magnitude of the speed, with the respect to the ground... maybe the poster of the question could be more clearer or something or I definitely need some work-out on motion principles.

if the ball's stationary, it must have zero speed. but since it has a speed, according to the question (70 mph), how is it stationary? (note: its velocity=0 relative to the train, that i agree wholeheartedly). -mak10

let me put in basic terms... velocity is a vector, it has both magnitude and direction. speed is scalar... it has only magnitude. so whichever direction you throw the ball, it is NOT going to affect the speed at which you have thrown. the ball will still travel some distance from the point from it is thrown... but it doesn't possess a velocity relative to the train, since velocities are direction-dependent, they get cancel off. how dont know how to explain this more simply... or maybe i am getting something wrong here... but thats how i see it -mak10

what is this force called? what is its source?? are gravitons from the sun responsible for this and how do they manage to hold the earth in its orbit?? another question I had was regarding the attractive force of gravity. from the informative sites Severian gave (for which I am immensely grateful to him!!), this particular site writes: if gravity is not a charged property, then why does it attract?? -mak10

velocity and speed arent the same thing... well, not almost. the velocities simply cancel off, as the ball and the train are travelling in opposite directions. but their respective speeds remain the same. if i were to imagine your secario and use your line of reasoning, that the ball would just fall without travelling any distance because its travelling at the opposite direction to the train, then so will the train... coz its travelling at the opposite direction from the ball... !! -mak10

more the velocity... more the drag force, thats how I think they're related. and thus, at some point, the drag force upwards will equalize the weight downwards and the resultant force becomes zero... and the acceleration of the object is now effectively zero = object falling at constant velocity.

it wouldn't just 'stop' and fall.... it stops relative to the train, because the velocities cancel out... but thats not say that its not travelling at 70 mph. it will still have the same speed and thus move some distance, from the point where it is thrown.... and then fall at some point. -mak10

I am, susprisingly, facing the same problem... except that I am not in canada but I am still undecided on my career option! so i took all three bio, phy, and chem for A-levels... just to keep my options open but I would also like to know what is the most worthwhile science career right now (i am interested in all sciences, except computer science!!) that is most likely to boom in the 3 to 4 years. thanks! -mak10

there is a series of particle interactions and energy is transferred via this process with no net loss of energy as such... i understand that perfectly well. but since the interaction mechanisms like collision require energy... the photons, thus, must derive their energy source from somwhere other than their neighbouring photons themselves. to be more explicit, consider this quote from the cern website thats speaking about the elementary particles: so energy is required to start the interaction mechanisms which, in turn, transmit energy to other photons/gravitons by elastic collisions, with no net loss of energy. that is the energy.... the first, shall i say, stimulating energy is what I am looking for. so far i havent found any good explanations for even its existence although its existence is absolutely necessary. i will, in the meantime, have a look at the websites some more and see if i can find any info on this. thanx severian! -mak10