Friday
August 28, 2015

Posts by joseph


Total # Posts: 452

physics
A reciprocating compressor is a device that compresses air by a back-and-forth straight-line motion, like a piston in a cylinder. Consider a reciprocating compressor running at 150 rpm. During a compression stroke, 1.30 mol of air is compressed. The initial temperature of the ...
May 30, 2011

com
why is the sequence of your paragraphs important in an essay
May 27, 2011

calculus
let m and b be nonzero real numbers if the line y=mx+b intersects y^2=4px in only one point, show that p=mb
May 24, 2011

Life orientation
Name two institutions/community organistations that are involved in supporting or giving redress to water pollution disasters.explain how these organisations are involved in providing a safe and healthy environment.
May 22, 2011

COM
Do you know of anything I have left out?
May 18, 2011

COM
Here is my answer so far. Do you know of anything else I can add to it?? The steps that must be taken prior to writing and effective persuasive essay is to build an outline of ideas and thoughts, elaborate those thoughts and ideas, do some research on the topic, define your ...
May 18, 2011

COM
Thank you for all the research!!
May 18, 2011

COM
What steps must be taken prior to writing an effective persuasive essay? How will those steps contribute to the effectiveness of your final paper?
May 18, 2011

physics
570J is the correct answer
May 8, 2011

Science
If one object on the moon weighs 42 pounds how much would it way on earth? Why?
May 4, 2011

Physics
In lab, a meter stick has its center of gravity at the 45.5 mark. The stick is supported with a meter stick clamp at the 25.0 mrk. A 3.500 kg mass is hung at the 18.2 cm mark to maintain rotational equilibrium. Whats is the calculation of the counterclockwise torque provided ...
April 25, 2011

Com
I did not understand your responce, could you please clarify?
April 25, 2011

Com
What is the rythem of the authors writing in the below paragraph? 3. Individuals can be denied credit for a number of reasons. Individuals who are near limits on existing cards, have too much outstanding debt or too many accounts overall, have a history of late payments, ...
April 25, 2011

physics
Believe it or not, a plumb-bob does not hang exactly along a line directed to the centre of the Earth! Determine how far off true plumb a bob hangs in Cape Town. In which direction is the deviation (north, east, south, or west)? How would your answer differ for a plumb-bob in ...
April 21, 2011

algebra
Make up a word problem that uses a quadratic function and requires finding either a maxiumum or minimum value.?
April 14, 2011

English
And if you were asked to write a principals report for class?
April 3, 2011

English
What is a principals report?
April 3, 2011

Chemistry
A student titrates HCl with 0.0125M KOH. Starting with 50.00 ml of the acid it takes 40.0 ml of base to reach equilavence point. A. What is the concentration of the HCl? B. What is the initial pH of the acid solution? C. What is the pH of the reaction mixture after the ...
March 30, 2011

English
Are there any compounds besides and,but,or,nor
March 29, 2011

Chemistry
A student titrates HCl with 0.0125M KOH. Starting with 50.00 ml of the acid it takes 40.0 ml of base to reach equilavence point. A. What is the concentration of the HCl? B. What is the initial pH of the acid solution? C. What is the pH of the reaction mixture after the ...
March 29, 2011

Chemistry
A student titrates HCl with 0.0125M KOH. Starting with 50.00 ml of the acid it takes 40.0 ml of base to reach equilavence point. A. What is the concentration of the HCl? B. What is the initial pH of the acid solution? C. What is the pH of the reaction mixture after the ...
March 29, 2011

English - Debate writing
Ms Sue pls i'm writing for the motion
March 25, 2011

English - Debate writing
I have a homework on debate on the motion 'The youth should be blamed for indiscipline in the society ' .Please help of to raise points for the motion .
March 25, 2011

calculus
solve the initial value problem by seperation of variables du/dt=2t+sec2t/2u, u(0)=-5
March 18, 2011

chemistry
Express your answer as a chemical equation. Identify all of the phases in your answer. H3PO + Sr(OH)2=
March 10, 2011

math
HOw can I find the domain and range of this problem 4x^3-39x^2+93.5
March 8, 2011

2nd grade/math
bhgb,jg,gbhhvhhhftyt
March 8, 2011

Calc 2
a) find the partial derivatives of each, and just plug in 1 for x and 3 for y (values should be close to 0)/ b) in using the difference quotients, take the limit as h approaches infinity of both each derivative, plugging in 0.1 for x and y in each one. It's better that you...
February 27, 2011

Chem
You are given pH which is (-log[H^+] ). so first you take 10^-2 to get the Molarity of [H^+], then you convert 500 mL to Liters so divide 500 by 1000. Finally you take Molarity times volume in liters to get moles of H^+. 10^-2 = .01 500/1000 = .5 .01 * .5 = 5*10^-3 = Moles of ...
February 27, 2011

social studies
what is an arch that forms a celling or roof
February 24, 2011

social studies
specific group that plundered rome. 5 letters.
February 24, 2011

social studies
the general term for a variety of groups who attacked roman towns
February 24, 2011

social studies
type of art made from tiny pieces of stone
February 24, 2011

social studies
what was the name of a hired soldier
February 24, 2011

calc
I would greatly appreciate your help with a math equation needed for a science experiment I'm researching. The case is the following: there is a pit full of juice and a stream of water is flowing through the pit (so that the amount of water which enters also exits). The ...
February 22, 2011

algebra
ax/b + cx/d =e solve for variable x
February 7, 2011

Physics
Pa and Oz start walking at the same corner of a field whose south- west is bounded by a straight wall. Pa walks alongside the wall at 5.5 km/h while Oz sets off at 6 km/h along a straight foot path across the field which makes an angle of 50 degrees with the wall. Find the ...
February 5, 2011

Chemistry
Which of the following is(are) true for an exothermic reaction? [H = enthalpy] A) ƒ´H¢X > 0 B) ƒ´H¢X < 0 C) Hreactants > Hproducts D) Hreactants < Hproducts E) Hreactants = ƒ´H¢X The square means delta.
January 30, 2011

math
what number gives the same result when multiplied by 6 as it does when 6 is added to it?
January 25, 2011

Math
The length of a rectangle is twice its width if the area of the rectangle is 200 m squared, find its perimeter.
January 17, 2011

Physics
100 m from a traffic light, a motorist sees it to red. If he needs to accelerate at -1 m.s ^2 to stop at the traffic light, what is the initial speed, and how long did he take to stop?
January 13, 2011

Chemistry
C=3 ;H=2 and Cl=1. Therefore the empirical formula of the compound is C3H2Cl The others don't seem clear to me
January 10, 2011

Chemistry
1) C=3 ;H=2 and Cl=1 so the empirical formula of the compound is C3H2Cl. I seem not to get the others clear.
January 10, 2011

Physics
A man using a 70 kg garden roller on a level surface exerts a force 20 kgf at 45 degrees to the ground . Find the vertical force of the roller on the ground if he ; a) pulls the roller. b) pushes the roller.
January 10, 2011

Algebra-please check
Thank you
January 7, 2011

Algebra-please check
Could someone please check my solution-Thank you-DRWLS helped me set it up and I solved it, I think From the top of a mountain 150 feet high, Jessie stands at the safety rail on the edge and looks below. The angle of elevation from his bike on the ground to Jessie is 38 ...
January 7, 2011

Algebra II-please check
sin 38 = .6157 .6157 = 150/x 150/.6157 = 243.6
January 7, 2011

Algebra II
From the top of a mountain 150 feet high, Jessie stands at the safety rail on the edge and looks below. The angle of elevation from his bike on the ground to Jessie is 38 degrees, how far is Jessie from his bike.Please help me to set this up Thank you
January 7, 2011

Physics
2 forces acting at a point make angles of 25 and 65 degrees respectively with their resultant which has a magnitude of 150 N .Find the magnitude of the two components.
December 31, 2010

physics
3 stings are attached on a ring. 2 of the strings make 70 degrees angle and each is pulled with 7.0 N . What force must be applied to keep the 3rd string to keep stationary?
December 30, 2010

calculus
At the instant when the radius of a cone is 3 inches, the volume of the cone is increasing at the rate of 28.27433388 cubic inches per minute. If the height is always 3 times the radius, find the rate of change of the radius at that instant?
December 30, 2010

calculus
find the inverse: y= ln (x/(x-1))
December 27, 2010

Physics
Given the info provided, this is a simple Q=mc(delta)T question. Simply plug and chug. m=10kg c=specific heat = 900j/kgxC (delta)T= 5 C The answer should be 4.5x10^4 J
December 19, 2010

calculus
the tangent line to the curve y=1/3(x^3)-3x^2+11x+15 is parallel to the line 9x-3y=2 at two points on the curve.Find the two points.
December 13, 2010

Precalculus
Doing some test corrections and not seeing this....Please help: Verify. csc^4x - cot^4x = 2csc^2x-1
December 9, 2010

spanish
Do you mean a la uno voy a la clase ciencias? If so, it means "at one o'clock I go to science class."
December 9, 2010

Precalculus
Having trouble with this: Verify: csc^4x-cot^4x=2csc^2x-1 *the numbers after the carets are to the power of
December 9, 2010

Chemistry
When a 1.350g sample of element X is heated in a stream of chlorine gas 6.67g of XCl3 are formed.1.) What(write) is a balance equation for the reaction using 'X' for the element? 2.) Calculate the atomic weight of X. 3.)What mass of X is left unreacted? 4.)When 1.00 ...
December 9, 2010

Chemistry
When a 1.350g sample of element X is heated in a stream of chlorine gas 6.67g of XCl3 are formed.1.) What(write) is a balance equation for the reaction using 'X' for the element? 2.) Calculate the atomic weight of X. 3.)What mass of X is left unreacted? 4.)When 1.00 ...
December 9, 2010

physics
Two identical containers are open at the top and are connected at the bottom via a tube of negligible volume and a valve which is closed. Both containers are filled initially to the same height of 1.00 m, one with water, the other with mercury, as the drawing indicates. The ...
December 4, 2010

Statistics
A student studies for a statistics exam where all questions are true or false. A reputable source indicates that with studying the student has a 90% chance of answering each question correctly. There are only three questions on the test. What is the probability that the ...
November 28, 2010

physics help
ye i dont understand ho your explaining with the other guy who posted it. i dont know where you get any of your number from
November 8, 2010

Physics help please
The drawing shows a collision between two pucks on an air-hockey table. Puck A has a mass of 0.030 kg and is moving along the x axis with a velocity of +5.5 m/s. It makes a collision with puck B, which has a mass of 0.055 kg and is initially at rest. The collision is not head-...
November 7, 2010

Physics please help cant figure this out
im just not sure what formula exactly to use to solve each part a,b, and c
November 5, 2010

Physics please help cant figure this out
starting with an initial speed of 5.00 m/s at a height of 0.265 m, a 1.75 kg ball swings downward and strikes a 4.45 kg ball that is at rest, as the drawing shows. (a) Using the principle of conservation of mechanical energy, find the speed of the 1.75 kg ball just before ...
November 5, 2010

physics please help
for part a i got change in momentum right which was 1.8 then when i divided that by 4.05E-3 i got 4.44E-4 and it was marked wrong
November 5, 2010

problem solving
if a circuit has a 3.9k resistor and a 5/f capacitor find the current flow in the circuit at 0.005 seconds,if the maximum current flow in thecircuit is 1.5ma
November 1, 2010

Science
The normal boiling point for acetone is 56.5 Celsius. The atmospheric pressure is 630torr. What would be the boiling point of acetone, delta Hvap = 32.0 KJ/mol. What would be the vapor pressure of acetone at 25.0 Celsius. Please help me with this problem. Thank you
October 31, 2010

Science
BP -164°C ΔHvap 8.136 kJ/mol sg 2.205 J/g°C MP -182°C ΔHfus 0.928 kJ/mol sl 2.41 J/g°C Using the data above for methane, CH4, calculate the heat needed to convert 150. g of liquid methane at -175°C to a gas at 25°C.
October 28, 2010

Science
which of the following are predicted by the molecular orbital model to be stable diatomic species N22-, O22-, F22-
October 23, 2010

Physics
In a two-dimensional tug-of-war, Alex, Betty, and Charles pull horizontally on an automobile tire at the angles shown in the overhead view of the figure. The tire remains stationary in spite of the three pulls. Alex pulls with force of magnitude 226 N, and Charles pulls with ...
October 8, 2010

Physics
A 400 kg rocket sled can be accelerated at a constant rate from rest to 1600 km/h in 2.0 s. What is the magnitude of the required net force?
October 8, 2010

science
In defining the sizes of orbitals, why must we use an arbitrary value, such as 90 percent of the probability of finding an electron in that region?
October 3, 2010

Science
If you drive 20 laps around a circular race track at 100 m/s what do you know about your speed, velocity and acceleration?
September 28, 2010

CHEMISTRY
The first-order reaction, SO2Cl2 ¨ SO2 + Cl2, has a rate constant equal to 2.20 ~ 10-5 s-1 at 593 K. What percentage of the initial amount of SO2Cl2 will remain after 6.00 hours?
September 27, 2010

chemistry
The first-order reaction, SO2Cl2 ¨ SO2 + Cl2, has a rate constant equal to 2.20 ~ 10-5 s-1 at 593 K. What percentage of the initial amount of SO2Cl2 will remain after 6.00 hours?
September 27, 2010

chemistry
decomposition of H2O2 to water and O2
September 26, 2010

chemistry
why is temperature of H2O2 measured in the graduated cylinder?
September 26, 2010

Math
Simplify please...thnks X/50=(312-X)60
September 23, 2010

Math Word Problem
The question is poorly worded. But that is the way I got the answer.
September 12, 2010

science
Balancing redox reactions Balance in acid solution 1. PH3+ I2 -> H3PO4 + I- 2. ClO3- + Cl- -> Cl2 Balance in basic solution Se -> Se2- + SeO3^2- BrO- + Cr(OH)4^- -> Br- + CrO4^2-
September 7, 2010

science
I need help with balancing redox reactions Balance in acid solution: 1) PH3+ I2 --> H3PO4+ I- 2) ClO3- + Cl- --> Cl2
September 7, 2010

phys
“There are many social and cultural contexts you interact with that strongly influence development. These contexts include people you interact with daily, neighborhood factors, and larger scale social and cultural variables. In order to fully understand how the ...
September 7, 2010

science
Balance in acid solution PH3+ I2-> H3PO4+ I-
September 6, 2010

chemistry
write the net ionic equation for the following : 2CuCl(aq)-> CuCl2(aq)+ Cu(s) 4NaCl(aq)+2H2SO4(aq)+MnO2(s)-> 2Na2SO4(aq)+2H2O(l)+Cl2(g) 3KOH(aq)+Fe(NO3)3(aq)->Fe(OH)3(s)+ 3KNO3(aq)
September 6, 2010

Science
ok, i got them. just want to make sure the answer are correct. thanks
August 20, 2010

Science
Give the conjugate acid of the following bases: a) NH2-, b) CO3 ^2-, c) HS-, d) OH-
August 20, 2010

Science
Is it O2(S) is denser right? Because it's solid
August 20, 2010

Science
thanks, i typed it wrong
August 20, 2010

Science
The normal melting and boiling point of O2 are -218C and 49.8atm. a)Sketch the phase diagram for O2. b) Which is denser, O2(S) or O2 (l)? explain.
August 20, 2010

science
Could I use STP( 760 torr and 273K) to plug in the equation ?
August 13, 2010

science
The equation require 2 pressure but there is only 1 in this problem
August 13, 2010

science
On top of one of the peaks in Rocky Mountain National Park the pressure of the atmosphere is 500.torr. Determine the boiling point of water at this location. The heat of vaporization of water is 40.7 kJ/mol? Show work for me please! Thank you
August 13, 2010

science
which would have a lower melting point, C3H6 or CH30H? explain please!
August 12, 2010

science
NH2-,NH3, and NH4+ have H-N-H bond angles of 105, 107, and 109. Explain this variation in bond angles
August 12, 2010

science
NH2-, NH3, and NH4+ have H-N-H bond angles of 105, 107 and 109. Explain this variation in bond angles.
August 10, 2010

science
which would have a lower melting point, C3H6 or CH30H? explain.
August 10, 2010

Science
Consider the following reaction: 2Na + Cl2  2NaCl ΔH = -821.8 kJ (a) Is the reaction exothermic or endothermic? (b) Calculate the amount of heat transferred when 5.6 g of Na reacts at constant pressure. (c) How many grams of NaCl are produced during an enthalpy ...
August 3, 2010

chemistry
I don't get which one is Tfinal, and Tinitial for both of them can you explain it? thank you
August 3, 2010

chemistry
A small “coffee cup” calorimeter contains 110. g of H2O at 22.0°C. A 100. g sample of lead is heated to 90.0°C and then placed in the water. The contents of the calorimeter come to a temperature of 23.9°C What is the specific heat of lead?
August 3, 2010

  1. Pages:
  2. <<Prev
  3. 1
  4. 2
  5. 3
  6. 4
  7. 5
  8. Next>>

Members