Questions Asked on
February 3, 2007

  1. Physics

    Two horizontal forces act on a 2.4 kg chopping block that can slide over a frictionless kitchen counter, which lies in an xy plane. One force is F1 = (3.4 N) i + (3.7 N) j. Find the acceleration of the chopping block in unit-vector notation for each of the

    asked by COFFEE
  2. Physics

    A worker drags a crate across a factory floor by pulling on a rope tied to the crate. The worker exerts a force of 450 N on the rope, which is inclined at 38° to the horizontal, and the floor exerts a horizontal force of 125 N that opposes the motion.

    asked by COFFEE
  3. HELP

    3. Page 213 #18 6,-5 4. Page 222 #24 4x+3=4 5. Page 223 #54 The y intercept is -4 and the line whose equation is 2x+5=8 6. Page 233 #24 Passing though(-2,-5) 7. Page 233 #52 Passing though (-4,2) and perpendicular to the line whose equation y1/3x+7 8. Page

    asked by Tina
  4. Physics! another one i need help with

    the velocity of the wind would be: (42km/h)cos(30)=36.37 After flying for 15 min in a wind blowing 42 km/h at an angle of 30° south of east, an airplane pilot is over a town that is 50 km due north of the starting point. What is the speed of the airplane

    asked by Troyyyy
  5. chemistry

    got another question for DrBob please? The composition of hydrogen selenide can be determined by heating tin (Sn) in a measured volume of gas. The hydrogen selenide is decomposed, producing solid tin selenide (SnSe) and hydrogen gas. If the temperature and

    asked by bertie
  6. Chemistry

    How many gas particles occupy a volume of 22.4 L at standard temperature and pressure? One mole of gas particles.

    asked by Bryan
  7. Physics/Math

    A person walks up a stalled 20 m long escalator in 79 s. When standing on the same escalator, now moving, the person is carried up in 60 s. How much time would it take that person to walk up the moving escalator? ratewalking= 20/79 ratemoving=20/60 time=

    asked by winterWX
  8. Chemistry

    Is Isopropyl alcohol an acid or a base? neither

    asked by Lisa
  9. physics

    The inner and outer surfaces of a cell membrane carry a negative and positive charge, respectively. Because of these charges, a potential difference of about 0.070 V exists across the membrane. The thickness of the membrane is 9.00*10-9 m. What is the

    asked by Ann
  10. Physics/Math

    After flying for 15 min in a wind blowing 42 km/h at an angle of 30° south of east, an airplane pilot is over a town that is 50 km due north of the starting point. What is the speed of the airplane relative to the air? This is a vector equation. I would

    asked by winterWX
  11. Literature

    Why and how is the handmaid's tale a realist text set in a fantasy world? Realist text? The major realist issues I see in that filthy book is the presence and manipulation of power, the control of sexual activities (gay, etc), and the role of an individual

    asked by Jessie
  12. physics

    One particle has a mass of 3.00*10-3 kg and a charge of +7.60 µC. A second particle has a mass of 6.00*10-3 kg and the same charge. The two particles are initially held in place and then released. The particles fly apart, and when the separation between

    asked by Ann
  13. Chemistry

    Let's do 1 and 2 and go from there. I will get you started. Take a 100 g sample. That means we have 19.9% C = 19.9 g C 46.7% N = 46.7 g N 6.67% H = 6.67 g H 26.7% O = 26.7 g O Find mols of these amounts. mols C = 19.9/12 = 1.66 mols N = 46.7/14 = 3.33 mols

    asked by DrBob222
  14. Chem/Physics

    1. How much work is necessary to accelerate a bullet having a mass of 5.0 g to a velocity of 1000. m/sec? This was on a chemistry problem set of mine, and it seems like a very physics-oriented question [I have not taken physics.] Could someone point me in

    asked by Jess
  15. Accounting 212 (Managerial)

    Could someone please assist in this matter. I'm trying to ascertain the straight-line discount amortization of a problem which is as follows. A company issues $4,000,000 of 6%, 15 year bonds dated January 1, 2007 that pay interest semiannually on June 30

    asked by Danny
  16. chem

    hi can anyone help how do i determine the molecular formular of the oxide of arsenic in its in its gaseous state the answer i got was 17.8 gl -1 for the density, which law do i use is it boyles law or charles law thanks A mol of a gas occupies 22.4 L at

    asked by bex
  17. Physics/Math

    A boy whirls a stone in a horizontal circle of radius 1.2 m and at height 2.0 m above ground level. The string breaks, and the stone flies horizontally and strikes the ground after traveling a horizontal distance of 10 m. What is the magnitude of the

    asked by winterWX
  18. Chemistry

    Heyy, okay I have this question about chemistry and its driving me nuts. It feels like I am so close but am just missing something. The question is: A vessel of 6.84 L in volume contains 3.61 L of pure water at 25°C. A partial pressure of 3.67 atm of CO2

    asked by Tracy
  19. Children's Literature

    Mrs. Edwards read "Owl Moon" to her class. As she read, she paused from time to time to allow the children time to think about the story. She used a different voice for each character. When she finished, she asked questions that helped her students

    asked by Karin
  20. Maybe you know this one..

    Heyy, I posted this before but it kinda got pushed down and ignored, and I was hoping maybe DrBob might have an idea since no one else did! okay I have this question about chemistry and its driving me nuts. It feels like I am so close but am just missing

    asked by Tracy
  21. algebra

    102 litre+0.01 m^3=? 102 liters is 102 * 10^-6 m^3 still confused x2+10=

    asked by Marcela
  22. Com215

    Give a copy of Appendix D to a friend or family member and ask that person to complete the table contained therein. Thank you for using the Jiskha Homework Help Forum. However, what are we to do with your question? Having no idea what appears in Appendix

    asked by Trenet
  23. macroeconomics

    Karmin wants to clean her house, finish her economics problem set, write her English essay, and spend time with her boyfriend. However, she only has time to choose one of these activities. Karmin chooses to finish her economics problem set. Hence, the

    asked by jenna
  24. Chemistry

    Heyy, okay I have this question about chemistry and its driving me nuts. It feels like I am so close but am just missing something. The question is: A vessel of 6.84 L in volume contains 3.61 L of pure water at 25°C. A partial pressure of 3.67 atm of CO2

    asked by Tracy
  25. history

    When were US children required to go to school? The earliest compulsory education was in Massachusetts Colony in the 1640s. Thereafter each colony and state enacted its own required school attendance laws. By 1918, all states required children to at least

    asked by Fidelia
  26. Ununhexium/atoms

    I don't understand, according to the periodic table at web elements; An isotope of Element 116 (292Uuh) was identified in the reaction of 248Cm with 48Ca. It is very shortlived and decomposes to a known isotope of element 114, 288114Uuq. How can it be that

    asked by Shove
  27. Algebra 1

    Driving down a mountain, Tom finds that he has descended 1800 ft in elevation by the time he is 3.25 mi horizontally away from the top of the mountain. Find the slope of his descent to the nearest hundredth. slope= descent/horizontal change 1800 feet to

    asked by Julie
  28. Math again!!

    Price: 64 cents/100 g= $_______/kg Quantity: 4kg Total cost: $______/kg x ________ =$_________ How many g in a kilogram? what does "kilo" mean? If 100 g cost $0.64 then 1000 g cost ?????

    asked by Marcela
  29. Chem

    Does my work here look right? 3. One mole of an ideal gas expands adiabatically into a vacuum. Calculate q, delta-e, w, and delta-H for the process. q= 0 [adiabatic] w= -Pext(V2-V1) w= 0 delta-e = w + q delta-e = 0 + 0 = 0 delta-h= delta-e + P(delta V)

    asked by Jess
  30. Physics

    magine a landing craft approaching the surface of Callisto, one of Jupiter's moons. If the engine provides an upward force (thrust) of 3270 N, the craft descends at constant speed; if the engine provides only 2190 N, the craft accelerates downward at 40

    asked by COFFEE
  31. math,correction

    Directions are: Perform the indicated division. Rationalize the denominator if necessary. Then simplify each radical expression. (18 + sqrt567)/(9) this is what i got: (41.811761799581315314514541782753)/(9)=4.6457513110645905905016157536393 Your answer is

    asked by jasmine20
  32. science

    hello jishka reply to me immediately wasn't that i told you i think this isnot a good website if i don't get the answer What kind of answer do you want? We are here to help you, but don't expect an immediate answer. We are not on line all of the time.

    asked by jeniffer
  33. chemistry

    Hi, Can someone please help??? looking for the empirical formula for Aliminium selenide if Se has a valency of -2 and aliminium 3! Thanks :) Wouldn't it be Al2Se3? Al is +3 and 3 x 2 = +6. Se is -2 and -2 x 3 = -6 And +6 - 6 = 0 and compounds must be zero.

    asked by bertie
  34. Math

    A golfer hits a ball off the ground with an initial velocity of 200 ft/s at an angle of 23 degrees. The green is 750 feet away. Will the shot make it to the green? State by how much it makes or misses the green.

    asked by Kyle
  35. Physics

    A boy whirls a stone in a horizontal circle of radius 1.2 m and at height 2.0 m above ground level. The string breaks, and the stone flies horizontally and strikes the ground after traveling a horizontal distance of 10 m. What is the magnitude of the

    asked by Troyyyy
  36. macroeconomics--help me!!!!!!

    Karmin wants to clean her house, finish her economics problem set, write her English essay, and spend time with her boyfriend. However, she only has time to choose one of these activities.Karmin chooses to finish her economics problem set. Hence, the

    asked by jenna
  37. biology

    What are two units of measure for the energy obtained from macronutrients? Energy units. A BTU (British Thermal Unit) is the amount of heat necessary to raise one pound of water by 1 degree Farenheit (F). 1 Joule (J) is the MKS unit of energy, equal to the

    asked by Kathlene
  38. Religion, Help

    Hello again, I hope someone could help me out. I have to work on a paper that uses 2-3 scholarly sources. This is what i have to do or the key elements of the assignment. -I have to trace the lives of Jesus and Mohammed historically -Compare what impact

    asked by Kailin
  39. math,help

    How or can someone set this up as an equation or what steps do i do? A garden area is 30ft long and 20ft wide. A path of uniform width is set around the edge. If the remaining garden area is 400ft^2, what is the width of the path? You submitted this a few

    asked by jasmine20
  40. math help please

    I am having a hard time understanding recprocial with fractions I would like to find a web site to help me understand this better I have a problem that is need to know if i have done it right the question is find the reciprocial of (-1/7)(14/3)(9) This how

    asked by tara
  41. science

    hi i want to ask you what does a root do to help plants grow? and what does a leave do to help a plant grow? could you please answer this queastion immediately? As I said to your later post, it is unrealistic to expect an immediate reply. However, you

    asked by jeniffer
  42. Molecular Formula

    How do you work out the molecular formula? Generally you convert grams to mols, then find the ratio of the atoms to reach other. But this is all generality. Why don't you post the entire problem, tell us what you know how to do and what you don't

    asked by L0bster_quadrille
  43. song

    i cant rember what a song was called i don't think its english and i think it was called every night or somthing and it had a woman and people doing flips and dancing round a fire in the night please help http://www.lyricsandsongs.com/song/25480.html Hope

    asked by lizzie
  44. bobprsly

    I do apologize but I looked in the past post and i don't remember asking about this problem in math. But if i did then I do apologize but i don't remember what you said in as the responce. If you can copy and paste it for me to see. Also I know that i have

    asked by jasmine20
  45. MATH!!

    hiii i needd help on this!! 30.47cm^2=___________mm^2 and 187000 cm^2+ 3.45m^2=_____m^2+_____m^2=________m^2 30.47 cm² = 3047mm² and 187000 cm² + 3.45m² = 18.7m² + 3.45m² = 22.15 m²

    asked by Anonymous
  46. susane

    I have a question concerning waves. What effect does increasing the tension in a vibrating string have upon wavelength? I was thinking that as the weight increases more standing waves are created. As more standing waves are created, the wavelength

    asked by Physics
  47. English essay

    I would be very thankful if you could correct my essay for grammar and spelling mistakes, thank you! Japanese music Lately Ifve been quite addicted to Japanese culture. Not that I havenft always been, but itfs getting worse and worse. My most recent

    asked by Juliane
  48. math-data management

    I have just started grade 12 U Data Management, and i do not understand tree diagrams. I need help with the following question: Draw a tree diagram representing the playoffs of eight players at the Australian open tennis tournament.

    asked by Sara
  49. chem

    could anyone tell me why the molecular formula of agas is not always the same as the empirical formula tnx It may be a dimer or a trimer. For example, CH is the empirical formula for acetylene but the molecular formula is HC(triple bond)CH or C2H2.

    asked by bex
  50. Road Signs

    What shapes are the most common for a road sign. Why is this shape used most often? http://www.trafficsign.us/signshape.html Think about how many uses you've seen per shape. Then make a decision! =)

    asked by Melthea
  51. Chemistry

    How would I explain how I arrived at the following EF in words?

    asked by MARK