Wednesday

July 29, 2015

July 29, 2015

Total # Posts: 2,883

**Physics**

A penny is placed at the outer edge of a disk (radius = 0.159 m) that rotates about an axis perpendicular to the plane of the disk at its center. The period of the rotation is 1.50 s. Find the minimum coefficient of friction necessary to allow the penny to rotate along with ...
*February 20, 2012*

**Physics**

A penny is placed at the outer edge of a disk (radius = 0.159 m) that rotates about an axis perpendicular to the plane of the disk at its center. The period of the rotation is 1.50 s. Find the minimum coefficient of friction necessary to allow the penny to rotate along with ...
*February 20, 2012*

**physics**

A 32.2-kg child swings on a rope with a length of 6.06 m that is hanging from a tree. At the bottom of the swing, the child is moving at a speed of 4.2 m/s. What is the tension in the rope?
*February 18, 2012*

**Physical Science**

Where did you get the 19.6 from? Also what formula are you using? The Vf^2 = Vo^2 + 2g*d....i've never seen that before
*February 17, 2012*

**Physical Science**

A 3-kg stone is dropped from a height of 100 m. Find its kinetic and potential energies when it is 50 m from the ground.
*February 17, 2012*

**SCIENCE**

I have a homework pqage for kindergarten that says Petal Patterns. Label each pattern. I'm not sure what the teacher is looking for. Can anyone help me?
*February 16, 2012*

**science**

what is the conclusion for what types of water will make a carrot softer
*February 15, 2012*

**biology**

1) I can't finish my homework due to this one question, please tell me where I can find this question, thanks! What are levels of protein structure of Angiosperms?
*February 14, 2012*

**physics**

A car drives off a sheer cliff, moving horizontally at 17.2 m/s. If the base of the cliff is 14.4 meters below, estimate how long does the car remains in the air.
*February 13, 2012*

**physics**

A car drives off a sheer cliff, moving horizontally at 17.2 m/s. If the base of the cliff is 14.4 meters below, estimate how long does the car remains in the air.
*February 13, 2012*

**chemistry**

how many grams are contained in 500.g of a 25% solution of H2SO4?
*February 13, 2012*

**physics**

A golf ball is struck with a five iron on level ground. It lands 92.7 m away 4.40 s later. What was (a) the direction and (b) the magnitude of the initial velocity?
*February 12, 2012*

**Literature**

theseus talking about plays
*February 10, 2012*

**chemistry**

Calculate the molarity of 2.05 L of a solution containing 1.51 g of dissolved KBr
*February 9, 2012*

**chemistry**

What is the molarity of an aqueous solution containing 43.7 g of glucose (C6H12O6) in 1.1 L of solution?
*February 9, 2012*

**Algebra**

Rachel and Lindsay are in third place in a race. Due to a time penalty, they must start the next leg 90 minutes after the second place team. If rachel and lindsay travel at an average rate of 16.8 mph and the second place team travels at an average rate of 14 mph, how long ...
*February 8, 2012*

**Science**

I learned the formula to be v=gt...why are you subtracting? Also what is vf and vi?
*February 7, 2012*

**Science**

a ball is thrown upward at a speed of 12 m/s. It will reach the top of its path in about: a) 0.6 sec b) 1.2 sec c) 1.8 sec d) 2.4 sec Please explain how you find the answer!!! I cannot figure it out
*February 7, 2012*

**pre calculus**

The graph of a one-to-one function is shown below. Draw the graph of the inverse function, f^(-1) , and submit it to the Dropbox. Please show your work
*February 5, 2012*

**physics**

A 200g mass attached to a horizontal spring oscillates at a frequency of 2.0 Hz. At one instant, the mass is at x= 5.0cm and has v= -30cm/s. find amplitude
*February 3, 2012*

**chemistry**

How can I group white substances into 2 groups according to their properties&list the properties of each group? Calcium carbonate, citric acid, sucrose, Phenyl salicylate, Potassium iodide,and Sodium chloride Also, which of them dissolves in water and which has solubility in ...
*February 2, 2012*

**chemistry**

How can I group white substances into 2 groups according to their properties&list the properties of each group? Calcium carbonate, citric acid, sucrose, Phenyl salicylate, Potassium iodide,and Sodium chloride Also, which of them dissolves in water and which has solubility in ...
*February 2, 2012*

**trig**

use the discriminant to solve for the smallest value of b that would make the roots of the equation x^2+bx+5=o imaginary
*February 2, 2012*

**trig**

a grocery store display consists of cases of soda. there are 15 cases at the base, and 1 case at the top. if there are 15 rows, how many cases are needed for the entire display? a) 180 b)30 c)130 d)15
*February 1, 2012*

**alg2/trig**

how much money would you earn in the fifth year? would you just plug in 5 into n to get your answer?
*February 1, 2012*

**Physical Science**

The string of a certain yo-yo is 80 cm long and will break when the force on it is 10 N. What is the highest speed the 200 g yo-yo can have when it is being whirled in a circle? Ignore the gravitational pull of the earth on the yo-yo.
*February 1, 2012*

**Physical Science**

So far for: A) w=mg =(70 kg)(25m/s^2) = 1750 N B) m=wg =(1750 N)(9.8 m/s^2) =1666 (I don't know what the units would be for this or if it even right) If you can help, it would be greatly appreciated!
*February 1, 2012*

**Physical Science**

Thank you!
*February 1, 2012*

**Physical Science**

A bicycle and its rider together have a mass of 80 kg. If the bicycle's speed is 6m/s, how much force is needed to bring it to a stop in 4 seconds
*February 1, 2012*

**Ochem**

What volume of 6.43% (wt.vol.) NaOCl solution is required to oxidize 221 mg of 9-fluorenol to 9-fluorenone? I'm not to sure of where to start with this problem. Please help!
*February 1, 2012*

**math**

a grocery store display consists of cases of soda. there are 15 cases at the base, & 1case at the top. if there are 15 rows, how many cases are needed for the entire display? a) 180 b)30 c) 130 d) 15
*January 31, 2012*

**Math**

The product of two consecutive odd intergers is 143. Find the intergers.
*January 31, 2012*

**alg2\trig**

a colony of 300 bacteria doubles each day. write an explicit formula to determine how many bacteria there would be on the nth day. how would you do this?
*January 31, 2012*

**Finance**

I am working on an assignment in which I need to put together a pro forma balance sheet. At the end of the assignment, I need to find the predicted values of accounts for the upcoming year. In 2011, Notes Payable was 11.28 million; Long Term Bonds were 7 million; Common Stock ...
*January 30, 2012*

**Physical Science**

Thank you so much!
*January 29, 2012*

**Physical Science**

A person dives off the edge of a cliff 33m above the surface of the sea below. Assuming that air resistance is negligible, (a) How long does it dive last? (b) and with what speed does the person enter the water?
*January 29, 2012*

**Math**

The perimeter of a geometric figure is the sum of the lengths of its sides. If the perimeter of a pentagon is 48 meters, find the length of each side.
*January 28, 2012*

**Chemistry **

A quantity of ice at 0.0°C was added to 25.0 g of water at 21.0°C to give water at 0.0°C. How much ice was added? The heat of fusion of water is 6.01 kJ/mol and the specific heat is 4.18 J/(g · °C). _g
*January 28, 2012*

**math**

in 1991 the life expectancy of males was 65.4 in 1998 it was 68.8 let e represent life expectancy in year t and let t represent number of years since 1991
*January 26, 2012*

**English**

Please tell me where I can find Articles about Energy Resource and issues. Thanks!
*January 24, 2012*

**world history**

the answer is ukiyo-e
*January 24, 2012*

**chemistry**

calculate the energy required to heat 1.00L of ice at -50.0C to steam at 180.0C
*January 17, 2012*

**Math**

What is the y-intercept of 4x+8y=12?
*January 17, 2012*

**Mathematics**

A farmer keeps hens and rabbits on his farm. One day, he counted a total of 70 heads and 196 legs. How many more hens than rabbit does he have? Explain your working please. Your help is greatly appreciated.
*January 15, 2012*

**math**

Sandy decided to give one-fourth of her CDs to Jenn. Then she gives one-half of the remaining CDs to Bob. If she is left with 6 CDs,how many CDs did she have to begin with?
*January 3, 2012*

**Math**

A wall hanging is x inches wide and has a height of 4x inches. If the perimeter is 40inches, what is the height in inches? Please help!
*December 31, 2011*

**Pre-Cal**

Find the area of each circular segment to the nearest tenth, given its central angle, x, and the radius of the circle. x= pi/8, r=7
*December 28, 2011*

**math**

the shorter leg of a 30-60-90 triangle is 9.4 inches long. find the perimeter.
*December 19, 2011*

**Math**

Haha, Steve is correct, I apologize for the guesswork. :/ It's g(x)= 1/3 -4/3x. Going off the work Reiny did, I am still rather clueless, so considering it's only two problems, I guess I'll just have to do some guesswork myself. Thank you for the help, though!
*December 19, 2011*

**Math **

I am not exactly sure of what I'm supposed to do in the following question: Describe and correct the error, given the functions f(x)=3x - 5 and g(x)=1/3 - 4/3. The first equation is as follows: g(-3)= 1/3 - 4/3 (3) =1/3 - 4 = -3 2/3 The second equation is: f(1)= 1/3 - 4/3(...
*December 19, 2011*

**chemistry**

A sample of cesium metal reacted completely with water, evolving 47.0 mL of dry H2 at 31°C and 769 mmHg. What is the equation for the reaction?
*December 13, 2011*

**physics**

A student investigates skateboarding down a slope. She times how long it takes her to skateboard between two lines on a sloping pavement. She varies the distance between the two lines and records her results in a table. Distance s/m time t/s Distance 2 Time 2.32 Distance 4 ...
*December 11, 2011*

**physics**

A student investigates skateboarding down a slope. She times how long it takes her to skateboard between two lines on a sloping pavement. She varies the distance between the two lines and records her results in a table. Distance s/m time t/s 2 2.32 4 4.23 9 8.22 11 9.53 The ...
*December 11, 2011*

**philosophy**

can anyone tell me is there any strong response aganist norcoss argument that if it wrong to kill puppies, so it is also wrong to support farming factory
*December 8, 2011*

**philosophy**

WHat is the strongest response against norcoss argument on puppies, pig and people
*December 8, 2011*

**Physics 201**

Suppose the mass of the wing is 0.258g and the effective spring constant of the tissue is 4.00E-4 N/m. Distance d1 = 3.03 mm and distance d2 = 1.76 cm. If the mass m moves up and down a distance of 2.08 mm from its position of equilibrium, what is the maximum speed of the ...
*December 5, 2011*

**english**

Am doing Autism and I have to give farther information. Thanks The cognitive part: I have...(1) Selecting attention, I have they absorve things..(2) Concrete processing, i dont have anything for this one. (3) Rote memory: I putted recalling.
*December 4, 2011*

**english**

How can you have Motivation, Forecast and Orientation in speech intorduction? like show the audience pictures etc?..thanks!
*December 4, 2011*

**physics**

a rod supports a 2.35 kg lamp. a)what is the magnitude of the tension in the rod? b)calculate the components of the force that the bracket exerts on the rod.
*December 4, 2011*

**English**

Am doing a project about Autism, what are the Cogngntive and pscohosocial of Autism and where can I find them? Thanks!
*December 3, 2011*

**grammer**

what is the adverb and verb for the sentence The players spent all day there.
*December 1, 2011*

**chemistry**

49.1
*December 1, 2011*

**math**

The gcf(a,b)=495 and cm(a,b)=31,185 Find possible values of a and b if a is divisible by 35 and b is divisible by 81
*November 29, 2011*

**V/CV OR VC/V PATTERN**

v/vc
*November 29, 2011*

**Chemistry**

Oops, sorry I meant .004 under initial moles of RNH2 not .001. Regardless I get an answer of 9.84 instead of 10.81
*November 26, 2011*

**Chemistry**

For part b of problem 2, I used ..RNH2 + HCl--> RNH3 + Cl I.+.001..+.002...0......0 C.-x......-x.....+x....+x E+.001-x..+.002-x..+x...+x Is this correct? My issue with these problems is that I don't know when to use the variables (like +x and -x for the C in ICE) or ...
*November 26, 2011*

**Chemistry**

Regarding your first post, I believe I used aspirin as the weak acid. In a previous problem which was related to these problems, it stated "aspirin is a weak acid with a Ka of 3.0x10^-5"
*November 26, 2011*

**Chemistry**

Sorry, one more question. For .........RNH2 + HCl ==> RNH3^+ + Cl^- initial...0....................... added...........0 added..........2.0 added..........4.0 etc change..................... the initial RNH2 is 0? Shouldn't it be the initial moles in the problem (....
*November 26, 2011*

**Chemistry**

For problem 1, if it were changed to 20 mL of the .07222M aspirin solution and 5mL of .2M NaOH, how would solving it differ? I tried ...........HA + NaOH ==> NaA + H2O initial..0014444.................. add..............001............ change...-.001.-.001.....+.001...+.001...
*November 26, 2011*

**Chemistry**

1.Calculate the pH of a solution prepared by mixing 20mL of the .07222M aspirin solution with 10mL of .2M NaOH. 2. Calculate the pH for the titration of 40mL of .1M solution of C2H5NH2 with .1M HCl for a)0 mL added and b)20 mL added c)40 mL added d)50mL added. Kb= 6.4x10^-4
*November 26, 2011*

**Chemistry**

For the ICE box, you are supposed to use the molarity of the aspirin. I did not realize that. Thank you so much for your help!
*November 26, 2011*

**Chemistry**

The answer that was in my answer key was 2.83 but I got 3.48. Is there something wrong in the calculations?
*November 26, 2011*

**Chemistry**

Aspirin is a weak acid with a Ka of 3.0x10^-5. Find the pH of a solution by dissolving .65g of aspirin in water and diluting it to 50mL. You can use RCOOH to represent aspirin. Molecular weight of aspirin is 180g/mol
*November 26, 2011*

**e-business**

In about 100 words, explain what kinds of features of characteristics a midsize business would seek in its electronic commerce software that would not matter to a smaller business.
*November 25, 2011*

**math**

How many ml of a 34% sugar solution must be mixed with 2 ml of a 54% sugar solution to make a 38% solution?
*November 20, 2011*

**Mathematics**

Given that a√b^2-c = 5k, find the value of: 1. k when a = 3, b = 6 and c = 20 2. c when a = 4, b = 7, and k = 11 Explain your working please
*November 16, 2011*

**physics**

A shopper in a supermarket pushes a loaded 31 kg cart with a horizontal force of 12 N. The acceleration of gravity is 9.81 m/s2 . a) Disregarding friction, how far will the cart move in 3.6 s, starting from rest? Answer in units of m
*November 14, 2011*

**physics**

A shopper in a supermarket pushes a loaded 31 kg cart with a horizontal force of 12 N. The acceleration of gravity is 9.81 m/s2 . a) Disregarding friction, how far will the cart move in 3.6 s, starting from rest? Answer in units of m
*November 14, 2011*

**Chemistry (Follow up post - Dr.BOB22)**

The first link seems to be broken.
*November 13, 2011*

**Chemistry (Follow up post - Dr.BOB22)**

Oh, I'm sorry. I wasn't really trying to put them together. I just wanted you to see what I understood about ionization. And then ask my question. Do you think you could help me understand lasers and plasma arcs connection to ionization levels? or point me to a website...
*November 13, 2011*

**Chemistry (Follow up post - Dr.BOB22)**

Ionization is when an electron is removed from an atom and ionization energy is the energy required to do this. "Electrons stream from the negative electrode to the positive electrode. In the process of moving from one electrode to the other they knock electrons in the ...
*November 13, 2011*

**Chemistry**

Thank you. My apologies for the repeated postings.
*November 13, 2011*

**Chemistry**

I have an assignment to 'Research ionization energy levels and come up with 3 real world applications' and was told to look up lasers, plasma arcs and neon lights. Hours later, (lol) I'm still having a little trouble. Is there any way someone can explain the ...
*November 13, 2011*

**CHEMISTRY**

Ionization is when an electron is removed from an atom and ionization energy is the energy required to do this. "Electrons stream from the negative electrode to the positive electrode. In the process of moving from one electrode to the other they knock electrons in the ...
*November 13, 2011*

**CHEMISTRY**

I have an assignment to 'Research ionization energy levels and come up with 3 real world applications' and was told you look up lasers, plasma arcs and neon lights. Hours later, (lol) I'm still having a little trouble. Is there any way someone can explain the ...
*November 13, 2011*

**CHEMISTRY**

I have an assignment to 'Research ionization energy levels and come up with 3 real world applications' and was told you look up lasers, plasma arcs and neon lights. Hours later, (lol) I'm still having a little trouble. Is there any way someone can explain the ...
*November 13, 2011*

**Chemistry**

I'm still having a little trouble. Is there any way you can explain the connection between lasers, plasma arcs and neon lights?
*November 13, 2011*

**Chemistry**

Do these three things have ionization energy levels? To be honest, I'm not quite sure how ionization works.
*November 13, 2011*

**Chemistry**

I have an assignment to 'Research ionization energy levels and come up with 3 real world applications'. I'm not so sure how to do this. Any help would be appreciated.
*November 13, 2011*

**college physics**

What distance will a 10 hp motor lift a 2000 lb elevator in 30 s? What was the average velocity of this elevator during the lift?
*November 11, 2011*

**Physics**

An 83.2-kg propeller blade measures 2.24m end to end. Model the blade as a thin rod rotating about its center of mass. It's initially turning at 175rpm. Find the blade's angular momentum, the tangential speed at the blade tip, and the angular acceleration and torque ...
*November 11, 2011*

**Mathematics**

If a piece of wood is 5 cm longer than a second piece, and 3/4 of the second piece is equal to 3/5 of the first, what is the length of the second piece? Explain your workings
*November 9, 2011*

**Mathematics**

Thanks
*November 9, 2011*

**Chemistry**

Classify the possible combinations of signs for a reaction's ∆H and ∆S values by the resulting spontaneity. A) Spontaneous as written at all temperatures. B) Spontaneous in reverse at all temperatures. C) Spontaneous as written above a certain temperature. D) ...
*November 9, 2011*

**Chemistry**

Calculate the pH of 100.0 mL of .0200 M pyruvic acid and .0600 M sodium pyruvate Calculate the pH of 100.0 mL of .0200 M pyruvic acid and 0.0600 M sodium pyruvate with 0.250 millimoles of H3O+ added.
*November 8, 2011*

**math PLEASE HURRY**

there are 24 students in a science class. Mr. Sato will give each pair of students 3 magnets. So far, Mr. Sato has given 9 pairs of students their 3 magnets. homw many more magents does Mr. Sato need so that each pair of students has excatly 3 magnets.
*November 8, 2011*

**math**

a developer wants to enclose a rectangular grassy lot that borders a city street for parking. If the developer has 336 feet of fencing and does not fence the side along the street, what is the largest area that can be enclosed and what are the dimensions that give this maximum...
*November 8, 2011*

**algebra**

I have no clue where to begin on this problem. Can some one help me please. One demographer believes that the population growth of a certain country is best modeled by the function P (t) =15 e^.08t, while a second demographer believes that the population growth of that same ...
*November 8, 2011*

**Chemistry**

Calculate the pH of the following 0.0500 M H3AsO4 and 0.0500 M NaH2AsO4?
*November 8, 2011*

**Chemistry**

Calculate the pH of the following 0.0500 M H3AsO4 and 0.0500 M NaH2AsO4?
*November 8, 2011*