Total # Posts: 1,616
A baseball is thrown straight up. The drag force is proportional to v^2. In terms of g, what is the y-component of the ball's acceleration when its speed is half its terminal speed and it is moving up? In terms of g, what is the y-component of the ball's acceleration ...
September 23, 2010
University Research-level Biology
Hello, this is an upper-level question, and I would sincerely appreciate help before Tuesday. I am reading a journal article, and there is one conclusion in it that I do not understand. It predicts a postsynaptic mechanism when EPSP amplitudes do not vary across trials, and a ...
September 20, 2010
6) We have afternoon classes on Tuesdays from 2pm to 4pm. 7) I prefer scientific subjects such as physics and maths to humanities. 8) We are tested orally twice a term and we get three written marks each term (is there a better way of expressing it??). 9) A calendar and an ...
September 19, 2010
At a picnic, there is a contest in which hoses are used to shoot water at a beach ball from three directions. As a result, three forces act on the ball, F1, F2, and F3 (see drawing). The magitudes of 1 and 2 are F1 = 55.0 newtons and F2 = 95.0 newtons. Using a scale drawing ...
September 12, 2010
PLEASE write 2x+y=5 in polar form. a. -sqrt5 = r cos (theta -27degrees) b. sqrt5 = r cos (theta -27degrees) c. -sqrt5 = r cos (theta +27degrees) d. sqrt5 = r cos (theta +27degrees) is the answer c.
September 6, 2010
An equilateral triangle is one in with all three sides are length. If two vertices of an equilateral trangle (0,4) and (0,0), find the third vertex. How mant of these triangles are possible? How would you slove this??
August 26, 2010
The total area enclosed by the graphs of y=10x^2x^3+x y=x^2+19x This is a really long problem I keep getting the answer of 20.25 but it is incorrect I don't know where I am going wrong?
August 17, 2010
Leggio Corporation issued 20-year, 7% annual coupon bonds at their par value of $1,000 one year ago. Today, the market interest rate on these bonds has dropped to 6%. What is the new price of the bonds, given that they now have 19 years to maturity
August 8, 2010
I dont understand how to write this equation. Write an equation relating the concentration for a reactant A at t=0 to that at t=t for a first-order reaction. Define all the terms, and give their units. Do the same for a second- order reaction. -Would it be the rate law ...
July 17, 2010
How would you solve this problem? C4H8(g)--> 2C2H4 Determine the order of the reaction and the rate constant based on the following pressures, which were recorded when the reaction was carried out 430 C in a constant volume vessel. Time (s) P(C4H8)(mmHg) 0 400 2,000 316 4,...
July 17, 2010
some child psychologists have concluded that___ is the strongest predictor of both scholastic and career achievement A. physical illness b. respect for authority c. emotional well being d inherited intelligence
July 14, 2010
An airplane flies 200 km due west from city A to city B and then 240 km in the direction of 31.0° north of west from city B to city C. (a) In straight-line distance, how far is city C from city A? (b) Relative to city A, in what direction is city C?
July 5, 2010
You are working in the product development department of a company that creates household products. Your team has come up with an idea for a revolutionary new cleaning product. Using the seven phases of new product development as a guide, describe how your company will develop...
June 7, 2010
A participant in a cognitive psychology study is given 50 words to remember and later asked to recall as many as he can of them. This participant recalls 17. What is the (a) variable, (b) possible values, and (c) score? I just don't understand what it all means. I've ...
May 28, 2010
A spherical convex mirror has a radius of curvature of magnitude of 20cm. At what distance from the mirror should an object be placed to obtain an image that is virtual, four times smaller and upright.
May 3, 2010
Mrs Munoz algebra class was collecting money for a party. The class decided that each student should give the same amount of money. They collected a total of $9.61. If everyone used 5 coins, how many nickels were collected?
April 19, 2010
is this correct? 1.a jar contains 5 white, 15 violet,and 21 blue marbles. a marble is drawn at random. P(violet or white) answer: 5x15x21= 1575 15x5=75 75/1575= 1/21 2. a number from 10 to 16 is drawn at random. P(a number greater than 14) answer: 2/7
April 8, 2010
find the number of possible choices when you choose one item from each category. 1. 3 hats, 7 shirts, 13 scarves 2. 6 pens, 2 nbk 3. 4 cars, 2 colors i don't get the question
April 8, 2010
is it reasonable to expect the heat of neutralization to be the same regardless of which acid is used? or should we expect each acid and base combination to have its own heat of neutralization?
April 8, 2010
In the neutralization of HCl and NaOH i was instructed to measure the temperature of the acid HCl prior to mixing the reaction components. I was to assume however, that the NaOH solution was at this same temperature. Is this a reasonable assumption?
April 7, 2010
Well, I know that the reaction is endothermic, because delta Hº is also positive. I just don't understand why delta G is positive, since the reaction seems to be spontaneous...
April 5, 2010
Help!! I am doing an assignment with 3 scenarios and I have got the first 2 but having trouble with the last. I have read through my chapter and searched webmd and other sites and still can't figure it out. Richard has noted over the past several weeks that he is having ...
April 5, 2010
I need help with this problem. I don't get how to do it or how they got that answer. A force of 50 pounds acts on an object at an angle of 45 degrees. A second force of 75 pounds acts on the object at an angle of -30 degrees. What was the direction and the magnitude of the...
March 29, 2010
The smallest object visible to the unaided eye is of 100 microns. If you use a microscope of m=1000, what is the size of the smallest object you can now see? (So=25cm) The answer is apparently 100nm. I am still confused as to why. Please help!
March 26, 2010
In the final step of making the nitro complex it involves the addtion of concentrated HCl. What are the role(s) of the HCl in this step of the synthesis? nitro complex: [Co(NH3)5(NO2)]Cl2
March 22, 2010
A mass spectrometer is used to separate isotopes. If the bean emerges with a speed of 374 km/s and the magnetic field in the mass selector is 1.5 T, what is the distance between the collectors for 235U+1 and 238U+1? The mass of 235U+1 is 235 u and the mass of 238U+1 is 238 u, ...
March 21, 2010
Two horizontal parallel wires which carry currents I1 = 45 A (top)and I2 (bottom). The top wire is held in position, the bottom wire is prevented from moving sideways but can slide up and down without friction. If the wires have a mass of 9.2 g per metre of length, calculate ...
March 21, 2010
I am still confused as to which direction the wires will rotate. Using the right hand rule, I found that the magnetic field of both wires will rotate counterclockwise (if you look from above and from the left side).
March 13, 2010
Two current carrying wires cross at right angles (like a + sign). Wire 1 has current directed horizontally to the left. Wire 2 has current directed vertically up. If the wires are not restrained, what statement best describes the motion of the wires? A) Wire 1 moves out of the...
March 13, 2010
We compare a silicon chip to a nerve membrane, with silicon having (about) twice the dielectric constant of the nerve membrane. Which of the following statements is true? A) 1cm^2 silicon chip has a higher capacitance than 1cm^2 nerve membrane. B) 1cm^2 silicon has the same ...
February 28, 2010
The frequency of an ambulance siren is 700 Hz. If a pedestrian on the side of the road hears the siren at 756 Hz approximately how fast and in what direction is the ambulance moving? The answer is 90 km/h and towards the person..im not sure how to come to this answer though......
February 22, 2010
This is a lengthy problem, but I really don't understand it. Any assistance given would be greatly appreciated. An analysis was done on a rock sample to determine its rubidium content. The rubidium content of a portion of rock weighing .350g was extracted, and to the ...
February 15, 2010