Tuesday

March 3, 2015

March 3, 2015

Total # Posts: 287

**physics**

Two blocks, each of mass m, are attached to the ends of a massless rod which pivots as shown in Figure 8-40. Initially the rod is held in the horizontal position and then released. Calculate the magnitude and direction of the net torque on this system. (Express your answer in ...
*November 10, 2009*

**Math - I still don't understand**

Well, I understand what you mean by the solution, but I am getting a really long decimal as the answer, so that's not an excat value. Please, can you help me some more?
*November 8, 2009*

**Math**

Angle x is in the second quadrant and angle y is in the first quadrant such that sinx=5/13 and cosy=3/5, determine and exact value for cos (x+y). I have no idea how to even start this question. Could someone please help me?
*November 8, 2009*

**Physics**

Rollercoaster has a dip that bottoms out in a vertical circle of radius r. Passenger feels seat of car pushing upward on her with a force twice her weight as she goes through the dip. If r = 20.0 m, how fast is rollercoaster going at bottom of the dip?
*October 21, 2009*

**Physics**

292 kg motorcycle is accelerating up a ramp that is 30 degrees above the horizontal. Propulsion force pushing the motorcycle up ramp is 3150 N. Air resistance produces a force of 250 N that opposes the motion. Find that motorcycle's acceleration.
*October 5, 2009*

**Math**

The y intercept is in the equation (0,1) You have to factor it to find the x intercepts: f(x)=(x-2)(x-1) (0,2) and (0,1)
*October 5, 2009*

**Physics**

1580 kg car is traveling with speed of 15 m/s. What is magnitude of horizontal net force that's required to bring the car to a stop in 50 m?
*October 5, 2009*

**math**

Solve the following inequality. Write the answer in interval notation abs value of x+4<4
*October 2, 2009*

**Math**

Thank You
*September 26, 2009*

**Math**

I did 2/3 + 1/3 I got 3/3. How do I do 7/15 + 9/20? I'm not good at adding fraction with different denominators.
*September 26, 2009*

**Physics**

A rocket moves upward for 3 seconds After 2 seconds, its speed is 10 m/s After another 1 second, its speed is 20 m/s Find instantaneous acceleration at t=2.5
*September 23, 2009*

**Science**

1 cm (cubed) = 10 mL 17 cm cubed x 10 mL = 170 mL
*September 23, 2009*

**chemistry**

I need help. I don't understand this one at all. My problem is the same, just the numbers are a little different. Potassium permanganate reacts with sulfuric acid as per the equation shown below. Indicate the excess reactant after the reaction of 7.90 g KMnO4 and 10.32 g ...
*September 19, 2009*

**math 11**

y=X^2 has an x-intercept of (0,0) and a y-intercept of (0,0), so yes
*September 16, 2009*

**physics**

Find the time it would have taken a horse to run: displacement: +1609 m average acceleration: +0.0105 m/s^2 initial velocity: +16.58 m/s
*September 16, 2009*

**math**

Find x-intercept for the line 9x+10y+16=0
*August 31, 2009*

**math**

f(x)=8 x^2 + x - 3 f(x+1) *ah i cant get this one please help!
*August 23, 2009*

**biology**

Which bacterial plates control for: 1) If the E. coli cells were transferred correctly: 2) If the E. coli cells can grow on LB: 3) If the Ampicillin is working correctly: 4) If the “stock” E. coli cells were contaminated with plasmid: Possible choices for each number...
*July 18, 2009*

**Percent Composition**

I figured out this percent composition problem and I got REALLY close answers, so I wanted to check in with someone to confirm if this is right. Which is the better ore for mining Aluminum: Either Al2(CO3)3 or AlPO4? For me the first one was the better percentage (22.85%) but ...
*April 21, 2009*

**Percent Composition**

I figured out this percent composition problem and I got REALLY close answers, so I wanted to check in with someone to confirm if this is right. Which is the better ore for mining Aluminum: Either Al2(CO3)3 or AlPO4? For me the first one was the better percentage (22.85%) but ...
*April 21, 2009*

**Biology**

Are there Japanese Beetles in Italy? I couldn't find out if there were or not. Thanks for looking this up!
*March 11, 2009*

**math**

the cost per hour of running an assembly line in a manufacturing plant is a function of the number of items produced per hour. The cost function is C(x) = 0.28x^2 - 0.7x + 1 where C(x) is the cost per hour in thousands of dollars and x is the number of items produced per hour ...
*February 23, 2009*

**Organic Chemistry**

Explain why the addition of bromine to trans-cinnamic acid takes place more slowly than the addition of Br2 to a normal alkene like 3-hexene or cyclohexene.
*January 24, 2009*

**Psychology**

How does having a negative self-schema affect one's social interactions? How does social intelligence affect one's responses in any given situation? How might a person's self-guides impact his or her perspective on the world?
*January 22, 2009*

**Biochemistry**

A peptide has the sequence: Glutamate - His - Trp - Ser - Gly - Leu - Arg - Pro - Gly What is the net charge of the molecule at pH 3, 8, and 11?
*January 21, 2009*

**Biochemistry**

A peptide has the sequence: Glutamate - His - Trp - Ser - Gly - Leu - Arg - Pro - Gly What is the net charge of the molecule at pH 3, 8, and 11?
*January 21, 2009*

**Organic Chemistry**

Okay, so I was thinking since this is an SN2 reaction, the leaving group would be Cl- or Br- when using either alkyl halide. The rate would increase because Br- is a weaker base than Cl- (because SN favors weak bases as a leaving group). Can someone correct me if I'm wrong?
*January 21, 2009*

**Organic Chemistry**

oops wrong area Anyway the reaction is sodium 4-chlorophenolate + chloroacetate ion --> 4-chlorophenoxy-acetic acid
*January 21, 2009*

**Organic Chemistry**

If sodium bromoacetate is used instead of sodium chloroacetate, how will the rate of reaction be affected?
*January 21, 2009*

**Psychology**

Children, like adults, experience depression and anxiety. How do the experiences of children who feel anxiety or depression compare to those of adults who feel anxiety or depression? Explain your answer.
*December 9, 2008*

**organic chemistry**

Partition (distribution) coefficient, k, of benzyl alcohol in hexane and water is 12.0. Choose for the correct equation for the amount of benzyl alcohol as x that you should use to calculate the amount of benzyl alcohol extracted with one 10mL portion of hexane from 500mg of ...
*November 25, 2008*

**college**

what is the Social composition on Corporate Greed?
*November 23, 2008*

**psychology**

Can someone help me with these questions, I am having trouble with them. 1. Traumatic events do not always result in a diagnosable psychological disorder. what factors determine how a person may be affected by one such event. 2. What are the four stages in meeting the ...
*November 15, 2008*

**organic chemistry**

An optical rotation study gives a result of +140 degrees. Suggest a dilution experiment to test whether the result is indeed +140 degrees, not -220 degrees.
*November 15, 2008*

**psychology**

Can someone help me with these questions, I am having trouble with them. 3. Traumatic events do not always result in a diagnosable psychological disorder. What factors determine how a person may be affected by one such event? 4. What are the four stages in meeting the ...
*November 15, 2008*

**organic chemistry**

A sample of 2-butanol has a specific rotation of -9.75 degrees. Determine the % ee (enantiomeric excess) and the molecular composition of this sample. The specific rotation of pure (+)-2-butanol is +13.0 degrees.
*November 15, 2008*

**english**

how does carbon dioxide affect the ocean?
*November 11, 2008*

**organic chemistry**

Determine the percent composition of your unknown mixture. My data for refractive indexes for acetone is 1.365 and water is 1.330. This is what my unknown mixture was composed of. How do I use this info to find percent composition of each compound?
*November 8, 2008*

**Psychology**

what are some of the ways that psychologists attempt to explain human behavior?
*October 28, 2008*

**chemistry**

This is for organic chem lab. I don't understand how to calculate the relative Rf values by setting ibuprofen to 1.00. For example, my Rf value for aspirin is 0.046, so how do I calculate the Rf relative to ibuprofen (1.00)? My experimental data for ibuprofen is 0.55 if ...
*October 28, 2008*

**Statistics**

What is the level of significance?
*October 12, 2008*

**Algebra**

Find the slope and y intercept. 3 - 1/2y=2x, 2y+9x+2=11+9x
*October 2, 2008*

**Compenstion & Benefits**

what methods do employers actually use to gauge their employees' evaluation of benefit packages?
*September 28, 2008*

**english**

Which sentence is correct?why I eat cake, carrots, pizza, and drink soda. I drink soda and eat cake, carrots, and pizza.
*September 26, 2008*

**English (Summer Reading Essay)**

Hi! well i was asked to read two books over the summer and answer 4 given questions in essay form but they also said each answer should be about 'one-half page' long...what exactly do they mean? do they mean half a page or a page and a half long? And also; they asked ...
*July 15, 2008*

**algebra**

Define a variable and write an inequality. Then solve. A local summer baseball team plays 20 games each season. So far, they have won 9 games and lost 2. How many more games must they win this season to win at least 75% of all their games?
*June 28, 2008*

**chemistry**

ANSWER: +.1 M M J
*May 12, 2008*

**psychology**

Can some one please help me with these questions I can not find the correct info. 3. Traumatic events do not always result in a diagnosable psychological disorder. What factors determine how a person may be affected by one such event? 4. What are the four stages in meeting ...
*April 18, 2008*

**biology**

Compare and contrast the processes of photosynthesis; aerobic respiration; and the two types of fermentation. Give examples of organisms that make use of each of these processes.
*February 5, 2008*

**Basic Math**

Which of the given numbers are composite? 0,1,15,19,23,31,49,55,59,87,91,97,103, 105
*January 22, 2008*

**english**

WHICH SENTENCE IS MORE CORRECT AND WHY? "Why can't I go with you?" asked Jake. or "Why can't I go with you?" Jake asked.
*January 8, 2008*

**history**

During the middle ages what were the roles of the Crusades on the power of the Church, the knights and how they strong-armed their role into power for the church.
*December 6, 2007*

**Physics**

thank you so much! I think I just overcomplicated the problem. thank you for making it much easier!
*October 18, 2007*

**Physics**

Four penguins are being pulled along very slippery (frictionless) ice by a curator. The masses of the three penguins are given below and so are two of the tensions. Find the penguin mass that is not given. 12kg---Unknown--111N--15kg---20kg--222N After drawing the free-body ...
*October 18, 2007*

**Probs & Stats**

a jury of people is chosen from 10 men and 12 women. How many ways can a jury of 6 men and women be chosen?
*October 16, 2007*

**Significant Digits**

There is also a way to do this in a graphic calculator... first put your calculator into degree and scientific mode Next type each problem in like this: (2.7,2) x (4.23,2) which will give you your answer. (*when u put the comma in, the calculator will show an E instead)
*September 28, 2007*

**Significant Digits**

Welcome
*September 28, 2007*

**Significant Digits**

you do 2.7 X 4.23=Y 10^2 X 10^2=10^4 and you get... Y X 10^4
*September 28, 2007*

**Math**

thanks
*September 28, 2007*

**Math**

A two-digit # whoses cube root is the square root of the sum of its digits
*September 28, 2007*

**Mathematics**

yeah, its 9.6
*August 30, 2007*

**Science**

I have a science question that I dont quite understand. Would you have to to have physical contact to exert a force? Not necessarily. Could we blow very hard and exert a force on something? When I was a kid I liked to make paper pin wheels and blow on them to see the pin ...
*August 19, 2007*

**econo**

. John has a paper route and spends all his weekly allowance on hamburgers and pop. The price of a hamburger is $2 and the price of a pop is $1. every week John buys 20 hamburgers and 10 pop. If the price of a hamburger rises to $4 (because of a ban on beef imports) and the ...
*May 25, 2007*

**Math**

A governor would like to find out how people in his state feel about state subsidized public art. How might a cluster sample be selected? I searched Google under the key words "cluster sampling" to get these possible sources: http://en.wikipedia.org/wiki/...
*March 27, 2007*

**AP CHEM**

I would really appreciate some help on this problem. =) At 218 C, Kc = .00012 for the equilibrium NH4HS(s)<==> NH3(g)+ H2S(g) Calculate the equilibrium concentrations of NH3 and H2S if a sample solid NH4HS is placed in a closed vessel and decomposes until equilibrium is ...
*March 15, 2007*

**to bobpursley**

An emergency breathing apparatus often placed in mines works via the following chemical reaction: 4KO2(s) + 2CO2(g) to make 2K2CO3(s) + O2(g) If the oxygen supply becomes limited or if the air becomes poisoned, a worker can use the apparatus to breath while exiting the mine. ...
*March 1, 2007*

**chem question i need help**

I need help on this question. Could someone give me tips on how to solve it? thanks An emergency breathing apparatus often placed in mines works via the following chemical reaction: 4KO2(s) + 2CO2(g) to make 2K2CO3(s) + O2(g) If the oxygen supply becomes limited or if the air ...
*February 27, 2007*

**chem**

which of the following is a chemical reaction? A) propane forms a flame and emits heat as it burns. B) Acetone feels cold as it evaporates from the skin. C) Bubbling is observed when potassium carbonate and hydrochloric acid solutions are mixed. D) Heat is felt when a warm ...
*February 20, 2007*

**American History:Antebellum Reforms**

What force or ideas motivate and inspire the effort to remake and reform American society during the anti-bellum years? Maybe some help here: http://en.wikipedia.org/wiki/Antebellum
*January 7, 2007*

**Chemistry**

Compounds like CCL2F2 are known as chloroflourocarbons, or CFCs. These compounds were once widely used as refrigerants but are now being replaced by compounds that are believed to be less harmful to the environment. The heat of vaporization of CCl2F2 is 289J/g. What mass of ...
*December 14, 2006*

**History**

For HW we have to do test corrections on our practice exam, so if any of you know the answers to these I'd appreciate it. =] 1. English Puritanism developed during the reign of Elizabeth I .. A) in reaction to the failure of the Elizabethan Religious Settlement to the ...
*December 10, 2006*

**AP euro help**

For HW we have to do test corrections on our practice exam, so if any of you know the answers to these I'd appreciate it. =] (I’ve eliminated the choice that was marked wrong for each) 1. English Puritanism developed during the reign of Elizabeth I .. A) in reaction ...
*December 10, 2006*

**Gases - van der waals**

It turns out that the van der Waals constant b equals four times the total volume actually occupied by the molecules of a mole of gas. Using this figure, calculate the fraction of volume in a container actually ocupied by Ar atoms (a) at STP, (b) at 100 atm pressure and 0 ...
*December 7, 2006*

**american hist**

why did the framers begin the constitution with "we the people..."? http://en.wikipedia.org/wiki/Democracy
*October 15, 2006*

**american hist**

-how were the federalists able to win ratification of the constitution? http://en.wikipedia.org/wiki/Federalist_Papers http://en.wikipedia.org/wiki/History_of_the_United_States_Constitution http://www.answers.com/topic/ratification-of-the-constitution
*October 15, 2006*

**chemistry**

"Newton's law tells us that Force= Mass x Acceleration. We also know that Energy = Force x Distance and Pressure= Force/Area. Using these relationships and table I-1 [I'll type it out], derive (do math stuff) the dimensions of newtons, joules, and pascals in terms...
*September 13, 2006*

**chemistry**

"Newton's law tells us that Force= Mass x Acceleration. We also know that Energy = Force x Distance and Pressure= Force/Area. Using these relationships and table I-1 [I'll type it out], derive (do math stuff) the dimensions of newtons, joules, and pascals in terms...
*September 13, 2006*

**orientalism of muslim and arab american**

I can't believe all the student over the years with the same questions from UOP. I am a student there as well. I am having a hard time with this assignment as well. I believe the assignment was created after 9/11 and has never been updated because there is nothing new on ...
*August 6, 2006*

**brain teaser help**

what does 50 = L with a W.N. mean?
*August 20, 2005*

**algebra anyone**

How to you compute the intercepts of a quadratic function? For the x-intercept, set x to 0. For the y-intercept(s) (if any), set y to 0.
*June 28, 2005*

**algebra**

: In case of a quadratic function, why are there two x-intercepts and one y-intercept? Let's say x^2 = y, which is a quadratic function. For every value of y, there are two possibilities for x. For example, if y is 4, x can either be 2 or -2.
*June 28, 2005*

**algebra**

Why are there two solutions in the quadratic equation and Why do you factor a quadratic equation before you solve it
*June 21, 2005*

**help!!!!!!!!!!**

When factoring a trinomial, why is it necessary to write the trinomials in four terms?" You keep posting this without any thinking. Can this be factored in four terms? 10x^5 + 2x + 17 Perhaps you are meaning factoring the "quadratic" (a polynomial of degree 2) ...
*June 16, 2005*

**math**

When factoring a trinomial, why is it necessary to write the trinomials in four terms
*June 16, 2005*

**math**

When simplifying a rational fraction, why do you need to factor the numerator and the denominator? Include two examples! I will be happy to critique your thinking on this. I wouldn't ask if I knew how to guess
*June 14, 2005*

**MORE MATH**

What is the factoring by grouping? When factoring a trinomial, why is it necessary to write the trinomials in four terms? I will be happy to critique your thinking on this. I do not understand to even answer it? (Broken Link Removed) (Broken Link Removed) How do we determine ...
*June 14, 2005*

**math**

When simplifying a rational fraction, why do you need to factor the numerator and the denominator? Include two examples! to get like terms Can you explain a little more? When you factor then you can cancel like terms Example: 12/3 (3)(4) ------- = 4/1 =4 3 i need to ask you a ...
*June 14, 2005*