Saturday

January 21, 2017
Total # Posts: 1,508

**Physics**

Please Help ! A child throws a snowball at a tree and it sticks to the tree. Does this motion defy the Law of Conservation of Momentum? Explain. The Law of Conservation of Energy states: "If there is no net force acting on a system of objects, the total momentum in that ...

*November 9, 2009*

**Physics**

If a 40 kg brick and a 400 kg brick each dropped from 1 m above a trampoline, find the lowest position of each brick. Assume the trampoline is a simple spring obeying Hooke's law with a k value of 12 000 N/m. So, I used mg(h+x)=1/2 k x^2 then solved for x in each case. ** ...

*November 6, 2009*

**math**

Cost= $10.00 for the belt $33.00 for the socks ($3.00 x 11) $3.00 for shipping 10+33+3= $ __________

*November 6, 2009*

**Physics**

you lost be. k= 12 000 N/m where are you getting 1 or 10

*November 6, 2009*

**Physics**

and how do i solve for x when it is on oth sides of the eq'n?

*November 6, 2009*

**Physics**

pe= potential energy?

*November 6, 2009*

**Physics**

okay, but what is the start of that eq'n? It looks similar to Eg=Ek ?

*November 6, 2009*

**Physics**

If a 40 kg brick and a 400 kg brick each dropped from 1 m above a trampoline, find the lowest position of each brick. Assume the trampoline is a simple spring obeying Hooke's law with a k value of 12 000 N/m. I know i must use Fs= kx, but where do I start? Do i find Fg at ...

*November 6, 2009*

**science**

A truck is stopped at a stoplight. When the light turns green, the truck accelerates at 2.2 m/s2. At the same instant, a car passes the truck going 12 m/s. Where and when does the truck catch up with the car?

*November 4, 2009*

**Physics**

ok i figured out what I did wrong for the (a). I also found (b). But I cannot seem to get the right answer for the kinetic energy lost in the collision.

*November 3, 2009*

**Physics**

I used the equation m1vf-m1vi=-m2vf+m2vi and got a velocity of 4.77m/s but that answer is incorrect. Am I not using the right formula for question (a)?

*November 3, 2009*

**Physics**

A barge with mass 1.7×105 kg is proceeding down river at 6.1 m/s in heavy fog when it collides broadside with a barge heading directly across the river. The second barge has mass 2.83×105 kg and was moving at 4.2 m/s. Immediately after impact, the second barge ...

*November 3, 2009*

**Maths**

start by multiplying by the lowest common denominator (in this case 4), simplify, then solve. 4(x/2) + 4(x/4)= 1 4/2=2 and 4/4 =1, therefore: 2x + x = 1 3x = 1 (3x)/3 = 1/3 x= 1/3

*October 30, 2009*

**Physics**

A pilot of mass 65 kg in a jet aircraft makes a complete vertical circle in mid-air. The vertical circle has a radius of 1.70 km at a constant speed of 215 m/s. Determine the force of the seat on the pilot at (a) the bottom of the loop and (b) the top of the loop. (Note that ...

*October 29, 2009*

**math**

wait, number two is wtong.. sorry!! 2. 2x-y=1 plug in 2 and 3.. 2(2)-3=1 4-3=1 1=1 so yes, (2,3) is the solution to the problem ((:

*October 26, 2009*

**math**

3x+4y=18 you just plug in 2 and 3.. 3(2)+4(3)=18 6+12=18 18=18 so yes, (2,3) is the solution for the first problem. 2x-y=1 again, plug in 2 and 3.. 2(2)-1=1 4-1=1 3=1 so no, it's not the solution for the problem hope I helped!

*October 26, 2009*

**French**

Can you please check these also Directions: Rewrite each sentence in the negative. 1. Il dit quelque chose à son copain. Answer: Non, il ne dit rien à son copain. 2. Et son copain écrit quelque chose. Answer: Et son copain n'écrit rien. 3. Il ...

*October 26, 2009*

**French**

Can you check these... Directions: Répondez que non Part I 1. Ta grand-mère travaille encore? Answer: Ma grand-mère ne travaille plus. 2. Ta soeur joue encore a foot? Answer: Ma soeur ne joue plus au foot. 3. Tu écris encore à ton amie Marie...

*October 26, 2009*

**English-interpreting quote**

What does this quote mean? "In the end, our society will be defined not only by what we create, but by what we refuse to destroy." I'm supposed to keep in mind the depetion of our ocean resources..

*October 25, 2009*

**algebra[please check]**

in questions 1 and 2, write an equation of the line in slope-intercept form. 1. the slope is -4/3; the y-intercept is -2. 2. the slope is 0; the y-intercept is -5. my answers: 1.y=-4/3-2 2. y=-5 ______________________ write an equation of the line that passes through the point...

*October 25, 2009*

**Physics**

Suppose that in the same Atwood setup another string is attached to the bottom of m1 and a constant force f is applied, retarding the upward motion of m1. If m1 = 5.30 kg and m2 = 10.60 kg, what value of f will reduce the acceleration of the system by 50%? thank you!

*October 24, 2009*

**algebra**

you are driving at a speed of 55 miles per hour to your sister's house. at 1pm, you are 150 miles from her house. write an equation that models the distance from you sister's house in terms of the number of hours since 1pm.

*October 24, 2009*

**Physics**

A 45 kg trunk is pushed 7.8 m at constant speed up a 30° incline by a constant horizontal force. The coefficient of kinetic friction between the trunk and the incline is 0.23. a)Calculate the work done by the applied horizontal force. b)Calculate the work done by the ...

*October 23, 2009*

**algebra 2**

2x+y=5 in slope form

*October 20, 2009*

**algebra 2**

ghngh

*October 20, 2009*

**Chemistry**

the heat of combustion of propane is -5.47MJ/mol. there is 1.50kg of propane available to burn. how many litres of water could be heated from 18.0 degrees Celcius to 63.0 degrees Celcius using the heat from the burning propane. assume that all heat lost by the propane reaction...

*October 20, 2009*

**algebra**

Write an equation in slope-intercept form of the line that passes through the given points: (-1/2,-1), (3,5/2). Also, write an equation in point-slope form of the line that passes through the given points: (6,-3), (-1,9). <soo sick of these.. please help!> thanks!

*October 19, 2009*

**algebra**

okay.. i get it i misunderstood your post.. thanks a lott xxx (=

*October 18, 2009*

**algebra**

I'm feeling horrible for not being able to do this. [I am the old rachel :(] could you explain it again? <ashamed>

*October 18, 2009*

**algebra**

write the equations in standard form of the horizontal and vertical lines that pass through the point 1. (2,4) 2. (-5, 4)

*October 18, 2009*

**algebra**

[<equationing (which isn't a word!)> hehe] thanks for the help! :)

*October 18, 2009*

**algebra**

write a linear equation to model the situation. you have walked 4 miles on a trail. you continue to walk at a rate of 3 miles per hour for 5 hours. please tell me how to do this!! thanks!

*October 18, 2009*

**algebra**

Thsnks again!! (=

*October 18, 2009*

**algebra**

1. write an equation of the line that passes through the point and has the given slope. write the equation in slope-intercept form. a. (3,2), m=1/2 b. (-3,2), m=1/2 _______ answers: a. y=1/2x + 1/2 b. y=1/2x + 7/2 ______________________________________ 2. write an equation of ...

*October 18, 2009*

**algebra 1**

write an equation in slope-intercept form of the line that passes through the points: 1. (-5,3), (4,-5) 2. (-1/2,-1), (3,9/2) _____ my answers: 1. y=-8/9x-5 2. y=3/7x+5/2 please check.. thnx

*October 16, 2009*

**world history**

compare in north america blacks and whites compare in latin america/carribean natives and foriegners and compare people or higher and lower status and compare free people to enslaved people

*October 4, 2009*

**Math**

When you walk around a polygon, at each vertex you need to turn either right (clockwise) or left (counterclockwise). A turn to the left is measured by a positive number of degrees and a turn to the right by a negative number of degrees. Find the sum of the measures of the turn...

*September 29, 2009*

**social studies**

what is a delta plain

*September 26, 2009*

**science**

dont know

*September 3, 2009*

**geometry**

a. If BC = 2x + 1, CD = 3x - 4 and BD = 22, find the value of x. b. Using the value of x, find BC and CD.

*August 30, 2009*

**4th grade math**

thirty six buses would be needed to carry the passengers and crew off three 747 jumbo gets. heres the question: how many buses fo one jet two jets. and how many jets for 180 buses and 252 buses and how many jets would be needed to carry the passengers on 264 buses

*August 25, 2009*

**French**

Thank you so much for all your help.

*August 23, 2009*

**French**

Directions: I wrote a paragraph saying my name, how old I am, my nationality, my hair color, eye color, what I like/not like to do, and 2 things about me. Could you please check my spelling, punctuation, ect.. and could you please give me a letter grade (I'm in 10th grade...

*August 23, 2009*

**Algebra**

How do I solve this multi variable equation for all the values of x and the value of r-s? 4x^2+20x+r=(2x+s)^2

*August 18, 2009*

**Math**

If sin (Theta Symbol) < 0 and sec (Theta Symbol) > 0, then (Theta Symbol) terminates in what Quadrant?

*August 14, 2009*

**math**

If a group of data has a mean of 19 and a standard deviation of 77.8, what is the interval that should contain at least 88.9% of the data?

*June 8, 2009*

**math**

I have a test tomorrow on inerior angles and need it explianed more thsn the teacher did,please help

*June 3, 2009*

**Cultural Diversity**

Explain the difference between Muslims and Arabs. o According to current (within the past two years) research and news reports, what are some of the changes the United States has made to policies concerning the treatment of Muslim and Arabic members of society? o List two to ...

*June 2, 2009*

**social studies**

some workers specialized in fishers,tailors ,printors,or what?

*May 17, 2009*

**Chem. Again**

28: You have a glass of pure water. Are chemical reactions occurring in the water? If so, what are they? If not, explain why not. 29: While investigating the effects of acid rain in your area, you discover a lake that is surprisingly resistant to changes in pH caused by acid ...

*May 12, 2009*

**Chemistry...Help?**

I've been trying to understand these two questions and I've re-read my textbook a dozen times but I still get confused. 27, A: Which is a stronger acid - sulfuric or carbonic acid? (Answer: Sulfuric acid.) 27, B: Imagine you have two glasses. One contains a solution of...

*May 12, 2009*

**Characteristics of Interpersonal Communication**

I am not understanding where to start on this or what is really being ask of me to do i feel the syllabus says one thing then appendix b says another. can someone help me

*May 5, 2009*

**9th grade**

y/6>y/12+1

*May 3, 2009*

**acrostic poem**

I need help writing an acrostic poem

*April 28, 2009*

**math**

David and Peter had $90 and $200 respectively. They were each given an equal amount of money. Then Peter had twice as much money as David. How much money did each boy receive?

*April 18, 2009*

**7th grade input/output patterns**

I am looking for the same thing,but don't go onto edhelper because they have nothing.

*April 17, 2009*

**Health**

At what point during the course of treatment of a new patient should notice of use and disclosure of health information, required under HIPAA, be given and why?

*April 14, 2009*

**Health**

Explain the subject matter jurisdiction of federal courts.

*April 14, 2009*

**Health**

What is res ipsa loquitur and what does it mean?

*April 14, 2009*

**Health**

If either contributory or comparative negligence doesn't exist anymore how would you be able to compare and contrast them?

*April 14, 2009*

**Health**

Compare and contrast contributory negligence with comparative negligence.

*April 14, 2009*

**Health**

If HIPAA rules are stricter than state law, which standard should you follow and why? What if the state law was stricter?

*April 14, 2009*

**Electronic Engineering**

What are the advantages and disadvantages of using a cause register or vectored interrupts from a hardware point of view.

*March 30, 2009*

**Math**

Let S = {Barnsley, Manchester United, Southend, Sheffield United, Liverpool, Maroka Swallows, Witbank Aces, Royal Tigers} be a universal set, A = {Southend, Liverpool, Maroka Swallows, Royal Tigers}, and B = {Barnsley, Manchester United, Southend}. Find n((A B)').

*March 26, 2009*

**Energy**

is the world running out of energy?

*March 26, 2009*

**Trigonometry**

How do you proove the identity tanxsin2x = 2-2cos^2x

*March 19, 2009*

**6th grade**

Do you have online readings and questions for my son, who is in 6th grade? I see lesson plans, but I don't see the information to give out. Please let me know about this, thank you.

*March 19, 2009*

**statistics**

a survey is to be conducted to determine the proportion of U.S. voters who support additional aid to African nations to fight poverty and HIV/AIDS. Of the proposed sammple sizes which is the smallest that will guarantee a margin of error of no more than 4% for a 90% confidence...

*February 28, 2009*

**trig**

how?

*February 23, 2009*

**trig**

sin^4 x = (3-4cos 2x + cos4x)/8 prove on one side please!

*February 23, 2009*

**Biology**

Where and how are tree seedlings raised?

*February 15, 2009*

**Science**

If a block could be molded into a flatter and longer shape, then which one would happen and can you explain? a. mass, volume, and density all would change. b. volume would change, but the mass and density would remaine the same. c. mass and volume would change, but the density...

*February 12, 2009*

**math**

if the answer is "start at (0,0) and move 3 units to the right, " what is the question?

*February 8, 2009*

**10th grade English**

The diffrence in your audiences religion is based on thier beliefs and how your explaining to them that you in a way are against them.The Jewish faith is one that is very strict and is not a strong supporter in women choosing their own destiny.Any other audience would proubly ...

*February 3, 2009*

**8th grade**

Go with number 3

*February 2, 2009*

**chemistry**

I got 51.5?

*January 24, 2009*

**Point Slope Form Algebra**

What is the difference between Y1=MX1+B and Y=MX+B

*January 20, 2009*

**Calculating Charge on a Polpetide**

10) What is the charge on the peptide CHEMISTRY at pH 8.3?? How would you go about this?Look at the ionizable groups? Thanks, Rachel

*January 19, 2009*

**science**

What are the two major functions of the appendicular skeleton?

*January 18, 2009*

**science**

How has a fly adapted to live in the desert?

*January 15, 2009*

**Algebra help 2**

name the property shown by the statement below 8+4*3-8+3*4

*January 6, 2009*

**Algebra**

On its first three plays in a football game, the offense gains 6 yards,loses 5 yards, and then gains 7 yards. Write an equation that could be used to find y, the number of yards needed on the fourth play for the overall 10-yard gain required for the first down. Could you ...

*January 6, 2009*

**Chemistry**

what is the name for the following coordination compounds or ions? 1. [Al(H2O)6] Br3 2. [Cr(NH3)6] Cl3 3. K3[FeF6] 4. [Zn(OH)4]-2

*December 4, 2008*

**Anatomy and Physiology**

Which of these two options demonstrate irritability and conductivity and thus transmit electrical messages from one area of the body to another area? 1. neurons 2. neuroglia

*December 1, 2008*

**earth comm fluid and spheres science**

can someone explain the relationship between ocean circulation patterns during an el nino event and atmospheric circulation?

*November 29, 2008*

**Science**

Ferns produce male gametes in what?

*November 11, 2008*

**History**

Thank you!

*November 9, 2008*

**History**

Who were the midnight judges in America during the 1800s? Also, can someone please explain the cause of Marbury vs. Madison and what the effect of Marbury vs. Madison was? Thank you.

*November 9, 2008*

**physics conservation of momentum**

yeah i kno how to calculate those 2. i got 5 and -5... so is momentum conserved? because change in momentum would be 5 - (-5) = 10 but some ppl are telling me momentum is conserved because they are the same values.

*November 8, 2008*

**physics conservation of momentum**

A 0.5 kg ball is thrown horizontally towards a wall with a speed of 10 m/s. The initial velocity is chosen to be the positive x-direction for this question. The ball horizontally rebounds back from the wall with a speed of 10 m/s in the negative x-direction. What is momentum ...

*November 8, 2008*

**Physics**

how come for part a. when i solve for Vf (which becomes V0 of the projectile motion), i get a negative value.. since i got this equation... 1/2ks^2+mgh+1/2mv^2 = 0 solving for v.. i get v = sqrt(-(2gh-ks^2/m) thats what is confusing me. so im not shure if i did it correctly.

*November 7, 2008*

**Physics**

A child's game consists of a block that attaches to a table with a suction cup, a spring connected to that block, a ball, and a launching ramp. By compressing the spring, the child can launch the ball up the ramp. The spring has a spring constant k, the ball has a mass m, ...

*November 7, 2008*

**physics**

a spring with spring constant k= 100N/m is at its equilibrium length a) how much elastic potential energy is stored in the spring? b) the same spring is stretched so that it is 6cm longer than it was. How much elastic potential energy is stored in the spring now? c) a ...

*October 30, 2008*

**French**

I have to write a short paragraph about where I have already traveled. Can someone check this for me? J’ai déjà allé à d’autres états des Etats-Unis et le Mexique. J’ai allé au Californie, l’Utah, Le Colorado, L&#...

*October 27, 2008*

**Science**

Explain what happens in the eye of the storm. Why can you survive the eye of the storm if you are inside and have shelter but instantaneously freeze if you are outside?

*October 23, 2008*

**Chemistry!!!**

Why does the ionization energy of Ca+ greataer than K even tho they have the same amount of e- why does Na have a relatively simple atomic spectrum while Cr has a very complex one?

*October 22, 2008*

**Chemistry**

Why do bromine and iodide have similar chemical properties?

*October 22, 2008*

**english**

In the following passage, a linking device has been omitted. Choose the word that would make the passage coherent: __ this technique won’t work for everyone, it helps many people get a good cache of ideas to draw on. 1. However 2. Although Please help with the question I ...

*October 19, 2008*

**english**

Rewrite this sentence into the active voice by filling in the blank: ORIGINAL: The agency conducted an investigation into the matter. REVISED: The agency __________ the matter. ORIGINAL: Attempts by economists at defining full employment have met with failure. REVISED: ...

*October 19, 2008*

**english**

Rewrite this sentence into the active voice by filling in the blank: ORIGINAL: The agency conducted an investigation into the matter. REVISED: The agency __________ the matter. ORIGINAL: Attempts by economists at defining full employment have met with failure. REVISED: ...

*October 19, 2008*