umer007

i think mass of each item in each bottle is the same. I thought that if we take the mass of each bottle and subtract by all bottles smaller than it for example we have 5 bottles wid masses: A: 5g B: 8g C: 9g D: 12g E: 13g if we do E - D, E-C, E-B, E-A, D-C, D-B, D-A, C-B, C-A, B-A. Then the smallest number of the subtractions will be the mass of one item since the mass of the bottle will automatically cancel out. However the problem with this is that we are assuming there are two bottles among the five where in one bottle there are x amount of items and in another bottle there are 2x amount of items. So 2x-x would yield x, mass of just 1 or x item. BUt if none of the bottles suit this pattern, if the closest I get is 5x - 3x, the result mass would be of 2x, 2 items not just one. So how would I know by doing the E-D, E-C..... subtractions that I am getting the mass of just one item or more than one. If it is more than one item, how would I know the number of items of which I am finding the mass, I would need to know the number of items to get the right answer for the mass of one item. Ne help would b much appreciated. Thx in advance.

could you plz. explain to me how to find the mass of one item or how to find the # of items in the bottles. Would i have to take the average of as many bottles as I can weigh or....I am hitting a brick wall here. I cant see the number of items in the bottle but I need to know how many there are by measuring the mass of the bottle with the items inside.

I am supposed to perform an experiment in class where I have to measure the mass of some little plastic bottles. I believe there are different coloured bottles and there are a certain number of items inside each coloured bottle (so each bottle with the same colour should have about the same mass). I am not sure how but this experiment is supposed to represent Millikan's experiment in which he tried to determine the elementary charge. Could someone plz help me out and lemme know how to go about finding the number of items in one specific coloured bottle. I m kinda lost so ur help would be much appreciated and also if some1 could describe how this relates to Millikan's experiment, that would also b helpful. Thx in advance.

can u plz tell me how to get copies of the old tests? Also have u heard anything abt Cliffs? Ive heard that it is better than Princeton's, but Princeton Review sounds much cooler...

Plz let me no what u guyz think from experience or even hrd from others which AP Bio book is the best to score 4-5 on the AP exam. Some of the best that ive heard are Cliffs and Princeton Review. Which 1 is the best? If one is to study mainly only from these prep books, which one is recommended? Thx.

wt abt the mammal and reptile @ 10 degrees. DO they both respire the same? or do reptiles respire more @ 10 degrees to keep their temp more constant since they are at more unfavourable temp compared to mammal? although in that case, wdnt the body temp of the reptile become warmer since respiration normally causes body temp to rise?

but wouldnt the 20 degrees mammal respire more since mammals prefer warmer temperatures? And 20 is warmer than 10, cant most mammals withstand high temps? So why would they need to cool off ?

How would the rate of respiration compare for a small reptile and small mammal of equal mass at 10 degrees celsius? How would rate or respiration compare for small mammal at 10 degrees celsius and another small mammal at 20 degrees celsius? How might rate of respiration compare for seeds that have been germinating for 0, 24, 48, 72 hours? I am very confused at these, I think it may have something to do with the fact that mammals are warm blooded where reptiles are cold blooded but I dont know how to explain it. And the last question Im lost. Plz help. Thx in advance

I need to simplify and solve. Could u plz gimme a step by step answer bcuz i get very confused in these type of cubed root questions. lim ((x+27)^1/3) -3) / x x->0 Its x+27 all under a cubed root subtract 3, all of this divided by x. Thanks in advance

I need to simplify and solve. Could u plz gimme a step by step answer bcuz i get very confused in these type of cubed root questions. lim ((x+27)^1/3) -3) / x x->0 Its x+27 all under a cubed root subtract 3, all of this divided by x. Thanks in advance

Which one of these oxidation reactions doesn't occur in cells? 2 H2 + O2 ------> 2 H2O + 114 kcal C6H12O6 + 6 O2 ------> 6 CO2 + 6 H2O + 686 kcal glucose palmitic acid + 23O2 -----> 16 CO2 + 16 H2O + 2338 kcal Please give a reason for your selection

is it possible to show how to get that 3.65 degrees mathematically? If so could you plz write it for me. Thx.

tan(θ°) = (viv) / (vih) = (1.28 ± 0.0676m/s) / (0.514 ± 0.0676m/s) = 2.55 ± 0.467 m/s θ° = 68.0 ± 3.65° This answer may not be correct to the decimal place but it shud b relatively close. Could someone plz explain to me how 3.65° becomes the uncertainty for the angle? Plz. explain very clearly and simply. Im in a hurry. THanks in advance

tan(θ°) = (viv) / (vih) = (1.28 ± 0.0676m/s) / (0.514 ± 0.0676m/s) = 2.55 ± 0.467 m/s θ° = 68.0 ± 3.65° This answer may not be correct to the decimal place but it shud b relatively close. Could someone plz explain to me how 3.65° becomes the uncertainty for the angle? Plz. explain very clearly and simply. Im in a hurry. THanks in advance

tan(θ°) = (viv) / (vih) = (1.28 ± 0.0676m/s) / (0.514 ± 0.0676m/s) = 2.55 ± 0.467 m/s θ° = 68.0 ± 3.65° This answer may not be correct to the decimal place but it shud b relatively close. Could someone plz explain to me how 3.65° becomes the uncertainty for the angle? Plz. explain very clearly and simply. Im in a hurry. THanks in advance

How will temperature and humidity affect the volume (length, width or height) and mass of the wood blocks??

what uncertainty would come from the electronic balance? can you explan a bit more

I did a lab recently where I had to measure length, width and height of different sizes of beach wood with a ruler (so gave each measurement 2 decimals). I also measured each piece on an electronic balance (the reading gave 2 decimals). I calculated the volume of each block and graphed against the mass. Could you plz. tell me as many sources of absolute uncertainties affecting my observations for each measurements and a brief explanation for each so I understand. I have this so far: parallax, edges of block not smooth. Could someone plz. explain parallax to me and how it affects my lab. Thanks in advance.

I have to create sort of a prototype i guess u wud say of the compound microscope on a metre stick. This will be done by holding lenses on top of the ruler, and magnifying the object atleast 3 times. I was planning on doing a sort of a compund microscope wid 2 lenses, each lens magnifying the object 2 times.. The one closest to the object being 200mm focal length and the one after 100mm focal length (converging lenses). I need to use the thin lens eqn (1/f = 1/di + 1/do) and the magnification eqn (M = -di/do = hi/ho) to set the object apart from the lens so in the end there wd b an image formed that wd b atleast 3X magnification of object. I need to make a scale diagram of this, but imnot sure how to find the distances for the object from the first lens centre, the distance of the image (which bcumz the object for second mirror) from the second lens centre and how i wd find the final image's distance. And same goes for height of object and both images. ANy help wd b much appreciated as i have hit a brick wall. Or any suggestions in changes wid magnification or lenses wud b appreciated as well. Thanks in advance

I'm sure its vry simple question but for sum reason I just cant solve it. 6cosx+5tanx=0 where x is equal or less than 2pie and equal or greater to -pie 3sinx-2cosx=0 then sinx/cosx=2/3, cosx can't =0 how can u move the sin's and cos's in one step like that and wt if it wz 3sinx+2cosx=0 then wt wd the eqn b? Cud ne1 give me sum pointers on how to solve identities, i seem to be having sum problems with them. Ne help wud b much appreciated. Thx.

well unfortunately my teacher told me hydrogen is not supposed to be released. He actually told me that the formation of malachite is actually a 2 step process so it wont work in one equation. If ne1 ever finds out plz post. O btw could CuCl have formed if the reaction was done fast in short amount of time, so kinda went uncontrolled and compounsd like CuCl couldve formed?

so 0.032% CO2 is present in the air, which is convrted to pCO2 10^-3.5 for the gases....rite. But are u sure about the hydrogen being released, is there any chance of telling hydrogen being formed by looking at the reaction or filter paper. Also cud sum1 plz xplain to me how Copper (I) Chloride could have been seen on the filter paper after the experiment was done. How would it be formed?

So theres no chance of any azurite formed in this reaction since it was in done in a lab rite. Also what does that "p" infront of CO2 stand for? What are those atmospheric pressure (10^-3.5 and 10^-1.36) measured in? Thx

Didnt really know where this thread should go, kinda related to physics but neways: Does anyone know the frequency range of a Xylophone? Also what are its typical waveforms? Thx

duz every1 agree wid this eqn? Is malachite formed in nature wid the same equation?