Posts by Christina
Total # Posts: 945

Physics Question
GIVEN: Two particles are created in a highenergy accelerator and move off in opposite directions. The speed of one particle, as measured in the laboratory, is 0.580c, and the speed of each particle relative to the other is 0.920c. QUESTION: What is the speed of the second ... 
Physics
A 22.8 kg turntable with a radius of 47 cm is covered with a uniform layer of dry ice that has a mass of 4.08 kg. The angular speed of the turntable and dry ice is initially 0.52 rad/s, but it increases as the dry ice evaporates. What is the angular speed of the turntable once... 
Physics Interference & Diffraction
Ooh wonderful! There is another problem similar to it...I am having trouble finding the # of fringes, but I think once I get help with that I can solve for the angle!!! GIVEN: Light of wavelength 585 nm falls on a slit 6.66×10−2 mm wide. Part A: On a very large ... 
Physics Interference & Diffraction
Given Information: Light of wavelength 631 nm passes through a diffraction grating having 485 lines/mm. Part A: What is the total number of bright spots (indicating complete constructive interference) that will occur on a large distant screen? *Answer: 7 (this is correct) Part... 
Math
6*5*3=90 
GeometryPSSA Practice
Which of the following quadrilaterals must have diagonals that bisect each other? Rectangle Parallelogram Rhombus Isosceles Trapezoid 
romeo and juliet
i have to write three six word biographies on Romeo and Juliet. Any ideas? :) 
Chemistry
How would I combine ions? like how would Sr be combined as a positve or negative ion? I DON'T GET IT! 
english
ya i cant find any because all they are doing in my part is talking and they don't use any props... so i don't know what to do .. 
english
i have to act out the first half of act3 scene 5 in romeo and juliet and i have to have some props. does anybody have any ideas for what i could use? 
electricity 188
hi my name is christina and i have an electrical question i need help with. i am taking power engineering electrical 188. the question is: how much will ity cost to use 6 lamps of 100 W each if they burn for 5 hours each evening in a month (30 days). the cost of electricity is... 
Geometry
A rectangular swimming pool that is 12ft by 15 ft has a deck of uniform width built around it. If the area of the deck is 198 square feet, find its width. 
Geometry
Okay i think i got it. a^2 + b^2 = c^2 6^2 + 8^2 = c^2 36 + 64 = c^2 sqrt of 100 = sqrt of c^2 10ft = C Is that right? 
Geometry
Okay.. whats the Pythagorean theorem again? 
Geometry
The foot of a ladder is placed 6 feet from a wall. If the top of the ladder is 8 feet up on the wall, how long is the ladder? 
Math
A rectangular swimming pool that is 12ft by 15 ft has a deck of uniform width built around it. If the area of the deck is 198 square feet, find its width. 
Honors Geometry
Thanks :) It is 30 by 44 feet :) 
math
what are the place valuse for decimals? 
Math
9187.5mg 
history
i have a bunch of history questions that i cant get. did Sir Walter Raleigh found Virginia? and were books the only publications available during the REnaissance? Who was Geoffrey Chaucer? and one more.. Did Queen Elizbeth and London officials have a cooperative relationship? ... 
Physical Science
The radius of a certain planet is 6.04x10^7 meters, and its mass is 5.19x10^26 kg. Find the density of this planet. (The volume of a sphere is given by (4/3)(pie)(r^3). Answer in units of grams/cm^3 
geography
how could i explain ethnic cleansing? 
science
the portion of your bodys weight which is bone is about? your heart and lungs are protected by your? sunlight aids the body in producing what? 
human anatomy
what is the cellular level of the digestive system 
SPELLING BEE
huh!!!!!!!!!!!!!sup anyway 
essay
I changed my mind. I am doing it on Christine Todd Whitman, the first and so far only female governor of New Jersey. Thanks again for the help! 
essay
Thanks! I did some prior research, and I think I will write about the current local mayor, although I am still undecided. 
essay
I am writing an essay on a courageous United States elected official and cannot pick a subject to write about. The official must have been elected since 1956; presidents are not recommended subjects. Any ideas? Any ideas? 
english
how would i illustrate the word blasphemy? Please Help!!!! Thanks! 
Physicshelp please!
You decide to use your body as a Carnot heat engine. The operating gas is in a tube with one end in your mouth (where the temperature is 37.0 C) and the other end at the surface of your skin, at 30.0 C. What is the maximum efficiency of such a heat engine? e=2.26% Suppose you ... 
math
how many ounces are in a pound? 
maths
how do you write 2.089 in expanded form 
Physics
I am beyond lost..I've never had any chemistry and our professor assumed that we had at least a basic knowledge...is there any way you could walk me thought this? 
Physics
ok, that makes much more sense... then i'm assuming that:n=2 for O2 and the m is .032 ???? M=n*m =2*.032 =.064 Then (1/2)(.064)(492)^2 =7746 ?????? 
Physics
Here is what I've done, hopefully you can identify where I've gone wrong.. =(1/2)(.032)(492)^2 =3873J 
Physics
Oxygen (O2) has a molar mass of 32.0 g/mol [.032kg/mol]. What is the rootmeansquare speed of an oxygen molecule at a temperature of 310 K? Vrms=492 m/s What is its average translational kinetic energy at that speed? Kav= ?? J I am having problems with the second half, ... 
physics help please :)
I'm not getting the correct answer.. this is my work: Q=214.374/4.18 =51.286 51.286=(50)(10^3)T T=.001 Do I need to convert the T to something else? It says to have it in C, which I think it's already in... 
physics help please :)
From a height of 35.0 m, a 1.25 kg bird dives (from rest) into a small fish tank containing 50.0 kg of water. What is the maximum rise in temperature of the water if the bird gives it all of its mechanical energy? (delta)T= ?? degrees C 
physics help please :)
From a height of 35.0 m, a 1.25 kg bird dives (from rest) into a small fish tank containing 50.0 kg of water. What is the maximum rise in temperature of the water if the bird gives it all of its mechanical energy? (delta)T= ?? degrees C 
Physics I'm stumped
Europa, a satellite of Jupiter, appears to have an ocean beneath its icy surface. Proposals have been made to send a robotic submarine to Europa to see if there might be life there. There is no atmosphere on Europa, and we shall assume that the surface ice is thin enough that ... 
Physics
If the force on the tympanic membrane (eardrum) increases by about 1.50 N above the force from atmospheric pressure, the membrane can be damaged. When you go scuba diving in the ocean, below what depth could damage to your eardrum start to occur? The eardrum is typically 8.20 ... 
Physics
At the time this problem was written, the price of gold was $427 per ounce, while that of platinum was $866 an ounce. The "ounce" in this case is the troy ounce, which is equal to 31.1035 g. The density of gold is 19.3 g/cm^3 and that of platinum is 21.4 g/cm^3. a)If... 
Physics
It is reasonable to assume that the bulk modulus of blood is about the same as that of water (2.20 m). As one goes deeper and deeper in the ocean, the pressure increases by 1.0*10^4 Pa for every meter below the surface. If a diver goes down 33.0 m (a bit over 100 ft) in the ... 
Physics
In the Grimms' fairy tale Rapunzel, she lets down her golden hair to a length of 20.0 yards (we'll use 20.0 m, which is not much different) so that the prince can climb up to her room. Human hair has a Young's modulus of about 490 MPa, and we can assume that ... 
Physics
I did that and I'm still getting a wrong answer... Is it possible that my calculations are wrong somewhere else?? I'm at a loss... 
Physics
It is reasonable to assume that the bulk modulus of blood is about the same as that of water (2.20 GPa). As one goes deeper and deeper in the ocean, the pressure increases by 1.0*10^4 Pa for every meter below the surface. If a diver goes down 33.0 m (a bit over 100 ft) in the ... 
Physics
I'm still getting A wrong.... F=(1.474*10^9)(7.81*10^5)/(.25) *.0125 =5755.95 Pa 
Physics
The Achilles tendon, which connects the calf muscles to the heel, is the thickest and strongest tendon in the body. In extreme activities, such as sprinting, it can be subjected to forces as high as 13.0 times a person's weight. According to one set of experiments, the ... 
math
Find the surface area of the right prism. The height is 2.5 cm, the lenght is 8 cm, and the width is 5.3 cm. This is confusing. I need help. 
Physics
The outstretched hands and arms of a figure skater preparing for a spin can be considered a slender rod pivoting about an axis through its center. When the skater's hands and arms are brought in and wrapped around his body to execute the spin, the hands and arms can be ... 
Physics
I'm on the change in KE part and this is what I get: KEf=(1/2)(2.5*10^2)(.150*7)^2 =.01378125 KEi=(1/2)(2.5*10^2)(.300*1.75)^2 =.0034453125 I'm not quite sure what to do with these two numbers... I subtracted KEi from KEf, but was told I had "rounding error"... 
Physics
A small block on a frictionless horizontal surface has a mass of 2.50×10−2 Kg. It is attached to a massless cord passing through a hole in the surface. The block is originally revolving at a distance of 0.300 m from the hole with an angular speed of 1.75 rad/s. The... 
English
what is the indirect object in this sentence "Chandler gave her the magazine" 
Physics
To strengthen his arm and chest muscles, an 83.0 kg athlete 2.00 m tall is doing a series of pushups. His center of mass is 1.15 m from the bottom of his feet, and the centers of his palms are 30.0 cm from the top of his head. Find the force that the floor exerts on each of ... 
Physics
I can't seem to find where I've gone wrong... Volume=(1/4)PI(.25)^2*15=.736... Mass= V*7800= 5743.2... I=(1/3)M*15^2=430741.8... 10^6=(1/2)Iw^2 w=sqrt(4.64...) w=2.15... w*2[for the 2 blades]=4.309... I tried the above value and was incorrect. 
Physics
I can't seem to find where I've gone wrong... Volume=(1/4)PI(.25)^2*15=.736... Mass= V*7800= 5743.2... I=(1/3)M*15^2=430741.8... 10^6=(1/2)Iw^2 w=sqrt(4.64...) w=2.15... w*2[for the 2 blades]=4.309... I tried the above value and was incorrect. 
Physics
M=7800*[(1/4)*PI*(.25)^2*15] KE=(1/2[(1/3)M(15)2]w^2=10^6 KE=2.15... x2 (for the two blades) KE=4.31 would that be in radians or revolutions? 
Physics
How do I determine the volume of the blade so I can find the mass? I'm not quite sure what shape the figure actually is... 
Physics
Tidal Energy. If we model 2 blades as thin uniform steel bars 15.0m long and .25m in diameter, at what rate (radians/second and revolutions per minute) must they spin for a turbine to store 10^6 J of energy? Keep in mind that the density of steel is 7800kg/m^3 and density is ... 
Physics
A CD rotates at 500 (revolutions per minute) while the last song is playing, and then spins down to zero angular speed in 2.60 seconds with constant angular acceleration. The magnitude of the angular acceleration of the CD, as it spins to a stop is 20.1 radians per second ... 
chemistry
what is the name of the polyatomic ion (C2O4)1? 
grammar
books, magazines, newspapers, and movies are either underlined or italicized, while other titles (such as that of a tv show) are put in quotes. the former (books, magazines, newspapers, and movies) is generally italicized when written on the computer, but underlined when ... 
math
how do you find a percent like 19 out of 50 people like dogs 
vocab
what is a sentence using it??? 
vocab
I have to do a presentation on the word contempt. I need to think of a fun way to review it and all the other words people presented. Please give me ideas! thank you! 
science
how does the intertidal zone influence humans? 
Spanish
i am not exactly sure what you are asking, but if you are looking for the meaning of de Sra, i can tell you that Sra stands for senora, which means de Sra means from the woman OR of the woman. 
history
thanks. i tried the first site already, but could not find the information i needed. hopefully the third site will help. :) 
history
what are some of the natural resources found in maryland? 
science
how old is the sun and the planets? how did the solar system form? what is a good website i can get this information from? 
math
how do u factor these polynomials~ 5x^2  5x60 81x^4 18a^2b50b 
Algebra 2
3x+2y=6 6x3y=6 
Advanced Algebra
3(square root of 1)(2+5(square root of 1) 3(2+5) 9=x+6(square root of 1) 9=x+6 9+6=x 15=x 
History
This is so dumb, but what year did the Spanish America war begin? http://en.wikipedia.org/wiki/SpanishAmerican_War 
Science.
Whats the difference between a scientific theory and a regular theory? A theory may be about anything but a scientific theory is designed to explain some scientific principle. Why people shop at a certain store might be an ordinary theory but why AgCl is more soluble than AgBr... 
Managerial Economics
The MorTex Company assembles garments entirely by hand even though a textile machine exists which can assemble garments faster than a human can. Workers cost $50 per day, and each additional laborer can produce 200 more units per day (the same for each additional worker). ... 
english
If a person's name ends with "the third," do you capitalize "third?" Yes, but it would be preferable to use the Roman numerals (III in this case) after the name. DrWLS is right. Here's an example: Richard III John Edward Jones III See? 
english
what are the differences between... to wake and to awaken? AND to rouse and to arouse? Here are two discussions of the usage of these words. awake, awaken, wake (up): awake is usually an adjective: "I am awake." Awaken is always a verb, either transitive ("A ... 
english
which is right...? Pollution, costs of living, and the threat of global warming IS rising. OR Pollution, costs of living, and the threat of global warming ARE rising. The subject is plural (pollution, costs of living, and the threat...), so the verb needs to be plural, too. ... 
essay topic
I cannot think of a creative essay topic related to the subject of "energy efficiency in my home." Please help! You could write from the point of view of someone who is buying a brand new house and can select all the appliances  and then do so with energy ... 
arithmetic
you can email me if you want i have more. A man owned 75 shares of stock worth $50 each. The corporation declared a dividend of 8 percent payable in stock. How many shares did he then own? 81 shares but how? If a scow is towed at the rate of 3 miles an hour, how many hours ... 
science(chem) Dr.Bob (activity coeficent)
When a 0.1M solution of weak acid HA was titrated with a 0.1M NaOH. The pH measured when Volbase=1/2Voleq point was 4.62. Using the activity coeficents, calculate pKa. fA=0.854 and fHA=1.00 For this I'm confused once again. I know that using the activity coeficents I can ... 
math problems
thanks alot for giving me those sites but i already know this stuff. They don't teach how to read an aritmetic problem so its confusing to me what to do with them, when sometimes its so obvious i just need someone to actually explain it to me in a diffent ways, that i ... 
arithmetics
ok i have a few more questions. this question. If a barrel has a capacity of 100 gallons, how many gallons will it contain when it is twofifths full? I know its 40 gallons but how and why? this one also. the number of halfpound packages of tea that can be made up from a box ... 
arithmetics
ok i understand now what 3/4 means and i know what 1/2 of a cup is but what does 3/4 of a cup mean. You can do it with blocks but not with how much is in the cup. I don't understand. will someone help me? You can do it with blocks. Let four blocks equal a cup, then three ... 
science(chem) Please Please Please check by today
How many ml of 0.8M KOH should be added to 5.02g of 1,5 pentatonic acid (H2A) Mwt= 132.11 to give a pH of 4.4 when diluted to 250ml before the first eq point pKa1= 4.345 Is the answer 25.2ml? If that IS correct then I need help b/c I can't get that answer... I've got ... 
science(chem) Please check by today
I REALLY REALLY NEED this to be checked by the END OF THE Day since my finals are tomorrow and I need to know if this is the correct way to do this type of question PLEASE TELL ME IF IT IS CORRECT. I AM posting this again since nobody replied to the other one The total Carbon ... 
science( chem)
The total Carbon dioxide content (HCO3 + CO2) in a blood sample is determined by acidifiying the sample and measuring the volume of CO2 evolved with a van slyke manometric apparatuses. The total concent was determined to be 28.5 mmol/L. The blood pH at 37o was determined to ... 
science( chem)
When a 0.1M solution of weak acid HA was titrated with a 0.1M NaOH. The pH measured when Volbase=1/2Voleq point was 4.62. Using the activity coeficents, calculate pKa. fA=0.854 and fHA=1.00 For this I'm confused once again. I know that using the activity coeficents I can ... 
science( chem)
When 100.0ml of a weak acid was titrated with 0.09381M NaOH, 27.63ml were required to reach the equivalence point. The pH at the equivalence point was 10.99. What was the pH when only 19.47ml of NaOH had been added ? I'll just post my work and I need someone to check and ... 
science( chem)
Find the pH of a solution prepared by disolving 1.00g of glycine amide hydrochloride (BH+) (mwt=110.54g/mol) plus 1.00g of glycine amide (B)(mwt=74.08) in 0.10L PKa=8.04 I got pH= 8.21 Is that correct? This question actually has 4 extra parts but I wanted to make sure I got ... 
science(chem)
I posted this before but nobody replied so I'll post again... this is in reference to whether textbooks such as Fundamentals of analytical chem should be cited as a literature source in a lab report on the titration of wine with standardized NaOH IF I said that %tartaric ... 
science( chem)
Calculate the molar solubility of Mg(OH)2 in water I know Mg(OH)2=> Mg2+ + 2OH 2H2O=> H3O+ + OH Ksp= [Mg2+][OH]2 Kw= [H30+][OH] Mass balance [Mg2+]=2[OH] So.. [OH]=2[Mg2+]+ [H3O+] Charge balance is where I get kind of confused I know that the positive charge is ... 
science( chem)
For literature citation at the end of a lab report if only the text is used would that have to be cited as well? Or would it not be cited and on the page for literature citation I would type no sources cited? You have to cite anything and everything that is used along with the... 
science( chem)
For the lab of Determining the % of iron in an iron ore sample The instructions were to: 1) Weigh out btw 0.30.4g of iron ore 2) disolve in concent HCl (10ml) and 3ml of 0.25M SnCl2 3) add enough tin so the yellow color disapeared 4) heat until sample decomposes and disolves ... 
science(chem)
What is Zimmerman Reagent made of? (I know it is acidic b/c I was told after it burned a hole in my jeans) acid? You must mean ZimmermannReinhardt reagent (79 g MnSO4, 100 mL of concentrated H2SO4, and 200 mL of concentrated H3PO4, diluted to 1 L) Zimmerman reagent is equal ... 
science(chem)
For an example of charge balance in my text it says Write a charge balance eqzn for an aqueous sol that contains NaCl, Ba(ClO4)2, & Al2(SO4)3 The answer given is: [Na+] + [H30+] + 2[Ba+] + 3[Al3+]= [ClO4] + [NO3] + 2[SO42] + [HSO4] + [OH] I know that the rxns are: NaCl=&... 
science(chem)
For MassBalance eqzns, in my text it is described as "relating the equillibrium concentrations of various species in a solution to one another and to the analytical concentrations of the various solutes. Is the analytical concentration described, the molar concentration... 
science(chem)
Situation: KMnO4 solution left in buret for awhile...would it be okay to go and titrate with the same solution left in the buret later? And if solution is discarded and refilled later wouldn't the solution go and react with the light thus contaminating the new solution? ... 
science(chem&statistics)
I have to write a abstract for my paper I was wondering if it was better to write it at the beginning or the end of the lab report. If I was to eliminate 1 value as an outlier would I go and include that in calculations of the RSD? I would assume not since It would affect the ...