Tuesday

October 25, 2016
Total # Posts: 42,287

**Physics**

hf=vi*t+1/2 at^2 hf=1/2 *60*25^2 I am assuming the acceleration given is NET acceleration upward

*October 25, 2016*

**gse 122**

Y=k(D)+j(D^1/3) 6=27k + 3j 11=k/8+j/2 multiply second equation by 6, then subtract first equation from second. 6=27k+3j 66=3k/4+5j or 60=-k(3/4-27) solve for k then put that k into either equation, solve for j. Now solve for y when D=3

*October 25, 2016*

**Chemistry pH, acids, and bases**

HClO4 is a very strong acid, it dissociates completely. pH= log (.04)

*October 24, 2016*

**Math**

what is 4650x5?

*October 24, 2016*

**Physics**

Vf^2=Vi^2 + 2ad but a= force/mass solve for distance d

*October 24, 2016*

**Math Check Answers**

yes, no , yes

*October 24, 2016*

**Please help quick!!!!! History**

There are probably hundreds of business practices in that category. origins of capitalism establishment of marketing establishment of labor unions (guilds) establishment of wide use of money instead of bartering.

*October 24, 2016*

**Physics**

vf=vi+at but a=force/mass solve for vf.

*October 24, 2016*

**Physics**

work=force*distance*cos56 force=mass*9.8N/kg work done=change in gpe

*October 24, 2016*

**physis**

weigh=mg=.04 mass= .04/9.8=4.08grams in liquid: weight= mg-bouyancy = mg-volume*density=mg-V*300g/liter .024=4.08-v*300g/liter v= = 4.06 grams*1000cm^3/300g = 13.52 cm^3 check all that. 2. volume=mass/density=1/(9.8*E3) volume= 102 cm^3 bouyancy= 102cm^2*1g/cm^3 apparent ...

*October 23, 2016*

**Physics**

Hmmm. If -6N was exerted on ball 1, then 6N was exerted on ball2 6*.1=.2w w=3m/s

*October 23, 2016*

**Physics**

70 degrees? what direction?

*October 23, 2016*

**phy101**

I think you need the distance between A and B. Lets call the distance x. V(x/2)^2=2 a (x/2) or v at half way is sqrt(2*1.2)(x^2/4) so v average for the first half trip is half that, or vavg=sqrt(2*1.2*x^2/16) but this is the same average speed on the second half... so time=x/...

*October 23, 2016*

**Physics**

total energy at launch=total energy at top 1/2 m v^2+ mghi=mgIhmax) 1/2 (7.4^2)+9.8(1.3)=9.8(hmax) solve for hmax time? hmax=hi+vi*time-1/2 g t^2 solve for time t.

*October 23, 2016*

**science**

Molearity=mass/molmass *1/volumeinliters mass=M*molmass*volume =.1*40(I think, check that)*1 grams or 4 grams pellets check the mol mass NaOH

*October 23, 2016*

**Physics**

about 10micrometers /second depends on wire diameter, voltage, and current. https://en.wikipedia.org/wiki/Drift_velocity

*October 21, 2016*

**PHYSICS: PLEASE HELP A.S.A.P HMK DUE AT MIDNIGHT T**

hf=hi+vi*time-4.9t^2 1.8=21.9+vi*t-4.9t^2 and 58=vi*t solve for t in the second equation t=58/vi put that in the first equation, solve for vi Now, speed just before impact vertical speed=9.8*t speedtotal=sqrt(vi^2+verticalspd^2)

*October 21, 2016*

**Math *corrected myself***

slope=(940-638)/8=37.75 each 2 years best estimate: 2*slope+940=75+940= 1015 best answer above 1100

*October 21, 2016*

**Chemistry**

specifies the principal shell of the orbital, however, I would not use the word "shell", as it misleads...energy orbital level is a better term. Surely you are not being taught that electrons are "orbiting" the nucleus like tiny planets. https://www.quia....

*October 21, 2016*

**Math**

(2.56E6)*(3.56E2)= Put that in your google search window. (2.52E7)/(4.05E5)=

*October 21, 2016*

**algebra**

f(5)=a/5=-10 a=-50 f(x)=-50/x

*October 21, 2016*

**P.E.**

You cannot spin the ball with one hand. The ball must leave both hands evenly though most referees are okay as long as you don't intentionally spin the ball.[4]

*October 21, 2016*

**Math**

see this post http://www.jiskha.com/display.cgi?id=1477089074

*October 21, 2016*

**Math Please Help**

demand=supply is x + 3p - 565=x - 16p + 480 19p=1045 p=$55 Now for quanitity x - 16p + 480 = 0 x=16(55)-480= 400 units

*October 21, 2016*

**Physics**

a use conservation of momentum to find final velocity of the combined particle. Then, knowing final and initial velocities, tabulate the KE ratio b. On this, you have to use conservation of energy and momentum, compute both final velocities.

*October 21, 2016*

**English Writingsh**

It almost makes sense thinking of chopsticks. I almost had the same thought two weeks ago in a Korean restaurant, I with a fork which did not work well.

*October 21, 2016*

**Politecnica**

Hmmmm.

*October 21, 2016*

**Math**

yes.

*October 21, 2016*

**Math**

cards average: 2/3= .66 quiz average= ,75 midterm= .533 class score so far: .66*10 + .75*20+.533*20 (6.6 + 15 +10.66)/.7 the .5 is because you dont have a final exam yet. grade to date: 32.3/.5= 65 on the basis of 100

*October 21, 2016*

**physics qui**

mass= density*volume = density*4/3*PI* r^3 = 5.517E6*4/3*PI* (6.37E6)^3 = 5.97323898e27 kg according to google calc. for your problem, nmber sig figures is three.

*October 21, 2016*

**math**

start with trunk labeled clothes, two branches called shoe1 and shoe2, off each shoe branch, two branches labled shorts1 and shorts2, and off each shorts branch two pants branches, ...

*October 20, 2016*

**Advanced Biology**

Hardy-Weinberg Law p^2 + 2pq + q^2 = 1 and p + q = 1 p = frequency of the dominant allele in the population q = frequency of the recessive allele in the population p^2 = percentage of homozygous dominant individuals q^2 = percentage of homozygous recessive individuals 2pq = ...

*October 20, 2016*

**algebra**

C(x)=n*x C(2)=2*.99

*October 20, 2016*

**Physics**

avgforce(time)=.15(35+25) solve for force

*October 20, 2016*

**Chemistry**

assuming no other acid is in the H3PO4 mix, then a) the equation 2H3PO4 + 3Ba(OH)2>>3H2O+Ba3(PO3)2 titration equation: nb*Ma*Va=na*Mb*Vb nb*molesacid=na*molesbase 3*75*.175/98=2*Molaritybase*.215 solve for molarity of base

*October 20, 2016*

**Math**

n+n+1+n+2=153 3n=150 numbers are 50, 51, 52

*October 20, 2016*

**Physics**

newtons law of cooling applies: http://www.softschools.com/formulas/physics/newtons_law_of_cooling_formula/93/ from the data of room temp, 80 to 60, determine rate r. then put that in the formula to figure time from 60 to 50. If you need help with this calculation, ask.

*October 20, 2016*

**Chemistry**

figure the mol mass of urea, as I remember it is ABOUT 56g/mol. so you want to multiply that by (250/1000)*.235

*October 20, 2016*

**Analytical chemistry**

1000 ppm, means 1000g 1000 ppm means .001g of Ca+2 ion, or .001/ 40.078 moles Ca, so you want then the same number of moles of C and O3 element, moles, mass Ca, .001/40.078, .001g C, ibid times 12.0107, 0.000299683118 3O, ibid times 3*15.9994, 0.00119761964 Now adding up the ...

*October 20, 2016*

**Algebra**

1/3 x -4+4=8+4 3x =36 x=12

*October 20, 2016*

**Science**

What is Fungi?

*October 20, 2016*

**Science**

if it has equal amounts in it, the density will be half between, or 9.7g/cm^3. So if density is more than that, it has more silver.

*October 20, 2016*

**Geography**

I can make no sense of your work.

*October 19, 2016*

**Chem**

What does it take to heat the ice to 0C, and melt? Figure that. 6*.5 cal/C*3+6*80cal=483 calories How much heat is released cooling steam to 100C, then condensing it? Figure that. 1*3*.48 cal + 533*1=535cal check those numbers. It appears from the above, there is about 52 ...

*October 19, 2016*

**algebra**

I am somewhat unclear on what you mean...this sounds much like a Julian calendar.

*October 19, 2016*

**Trigonometry**

(5.8/h)=tan55 solve for h.

*October 19, 2016*

**physics**

if in series, resistance = 12 ohms. current= Vapplied/12 Now, where is the voltmeter connected?

*October 19, 2016*

**Physics**

speed=sqrt(335^2+75^2) direction: arcTan75/335 E of S

*October 19, 2016*

**physics**

Q initial=10u*30=300u That charge then redistriubtes (equivalent capacitor=60uf C=Q/V V=Q/C-300u/60=5volts energy initial=1/2 CV^2=1/2 *10u*900=4500u Joules energy final=1/2 CV^2=1/2 60u*5^2 30*25u=750u So where did the energy go? A paradox? http://hyperphysics.phy-astr.gsu....

*October 18, 2016*

**G.p.**

Sum=21=A + Ar + Ar^2 sumsquares: 189=A^2+(Ar)^2 + (Ar)^4 21=A(1+r+r^2) 189=A^2(1+r^2+r^4) squaring the first equation: 21^2=A^2 (1+r+r^2)^2 441=A^2 ( (1 +2r+3r^2+2r^3+r^4) 441=A^2 (1+r^2+r^4)+A^2(2r+2r^2+2r^3) 441=189+A^2*2r(1+r+r^2) 441=189+A^2*2r(21/A) 441=189+42A solve for ...

*October 18, 2016*

**Chemistry**

What happens if you add 100 ml water (ice water, no ice) at zero C, then measure the final temperature?

*October 18, 2016*

**chem 1411**

S is -2, makes Ln+3

*October 18, 2016*

**Chemistry**

density=mass/volume=1.75g/(2.45^3)cm^3

*October 18, 2016*

**Chemistry**

from your equation, let x be concentration of H3O+ ka=x^2/(.1-x) but PH=2.37, or x=10^-2.37 x^2=10^-4.74 ka= 1.81970086e-5/(.1-0.0043) ka=0.00019014638=1.9e-4

*October 18, 2016*

**Chemistry**

You are diluting the acid 17/1.78 times, or 9.55 times That means one part acid, and 8.55 parts water. What is one part? .15L/9.55=15.7ml so, 8.55 parts water is 15.7*8.55=134.2 ml water. so add 15.7 ml of 17M acid to the water, stirring, (always acid to water).

*October 18, 2016*

**CHEM 1411**

the base is diprotic, Na*Va=Nb*Vb .0215Va=2*.0150*.235L solve for Volume of the acid, Va

*October 18, 2016*

**physics**

In which direction is the student accelerating? It matters. If accelerating upward, 1250=m(9.8+2.3) if acceleralting downward 1250=m(9.8-2.3) If in any direction other than upward or downward, it will be between these numbers.

*October 18, 2016*

**Science (Chemistry) Ratio of mole**

mass of O2: .234-.101 grams=.131g moles O2: .131/32=.004 Moles Mg= .101/24=.004 divide both by the lower Moles O2= 1 moles Mg=1 MgO2 is what you got.

*October 17, 2016*

**fountain of knowledge international academy**

I assume you mean Molarity when you type "mol". That is not an accepted substitution. I will do one, all are similar. B. If one has 0.75M solution, then concentration of the nitric acid is .75Moles/liter= .75Moles/liter*63grams/mole = .75*63 grams/dm^3 Because the ...

*October 17, 2016*

**fountain of knowledge international academy**

4X + 3O2>>2X2O3 well, four moles of X will react with three moles of O2. moles O2= 10g/32g= 10/32 so we need 4/3 of 10/32 or 40/96 moles of X. What is the mass of that? 56*40/96

*October 17, 2016*

**PHYSICS**

conservation of momentum: .5*2+.1*.25=.5V+.1*1.5 1+.025-.15=.5V V=2(.875)=1.75 m/s to right (which is impossible, of course as it had to just go thru thr right ball going slower. KE= 1/2 m v^2=1/2 *.5*1.75^2 J

*October 17, 2016*

**physics**

wf=wi+alpha*t 97=wi+7*a 28*2PI=wi*7+1/2 a *49 so you have two equations, two unknowns. Since you are intersted in a, solve for wi in the first equation, put it in the second, and solve for a.

*October 17, 2016*

**MATH**

hmmmm. It asks for demand equation, but gives answers in Inverse Price equation. Demand equation: demand=b-a*Price Inverse demand equation: P=Q/a+b where Q is demand, P price, a and b are constants. Data 40=1200/a + b 90=200/a + b subtract second from first -50=1000/a a= -20 ...

*October 17, 2016*

**math need help ASAP**

3/5 is a almost one 3/17 is small so the sum is about 1.

*October 17, 2016*

**physics**

you did not type enougth

*October 17, 2016*

**Physics fundamentals**

kinetic friction

*October 17, 2016*

**physics**

the charge has to be 1.6E-19 * 1E03 coulombs

*October 17, 2016*

**Physics**

work=mgh power=work/time=mg * velocity = 1500*9.8*2.5 watts

*October 16, 2016*

**Physics**

a. TanTheta=mu theta=arctan mu b. horizonal force resolves into an upward the plane component, and a normal component which increases normal force. friction=(mg+FsinTheta)mu downplane force=mg*sinTheta upplane force= F cosTheta so the question is what is theta such that ...

*October 16, 2016*

**Physics**

a. zero. Newtons third law. b. down, as the fan will propel the ship, as in an airboat.

*October 16, 2016*

**Physics**

If it is not moving, the fricion must equal the pushing force. if it moves at 29.5 N then 29.5 is the max static force

*October 16, 2016*

**chemistry help**

35I + 37((100-I)=100*35.5 solve for I, and 100-I

*October 16, 2016*

**Math**

gas used: 48+45.5 liters odometer: 1000 avg liters/km= gasused/1000

*October 16, 2016*

**Chemistry**

energy=planck's constant*speedlight/wavelength

*October 16, 2016*

**PHYSICS**

concentrate on b and d.

*October 16, 2016*

**Physics**

remember the orbital radisu is rmoon+altitude. Force=GMm/orbitRadius^2 and force= m v^2/orbitRAdius set them equal, solve for v. then, period T: v=2PI*orbitalradius/T solve for T

*October 16, 2016*

**Algebra**

H*.37+(50-H).22=13.25 H(.15)+11=13.25 H= 2.25/.15=15=expensive stamp (50-H)=35=cheap stamp

*October 15, 2016*

**Calculus**

even: f(x)=f(-x) odd: f(x)=-f(-x) a) 4(3)+5 ? 4(-3)+5 17? [7 neither b) (3)^2 -3-2 ? (-3)^3 -(-3)-2 4 ? 9 neither c) (2^4-2)/( 2^5 -2) ? ((-2)^4-2)/((-2)^5 -(-2)) 14/30 ? ( - 14/30) even do the last on these same way...

*October 15, 2016*

**Calculus**

I think you wanted to know how: multily numerator and denom by sqrt(3-x) + sqrt(3+x) lim ( 3-x -3-x) )/(x(sqrt(3-x) + sqrt(3+x)) lim(-2x/x(sqrt(3-x) + sqrt(3+x))) lim -2/(sqrt(3-x) + sqrt(3+x)) =-1/sqrt(3)

*October 15, 2016*

**Calculus**

see other post

*October 15, 2016*

**chemistry**

yes, better

*October 15, 2016*

**true**

h=1/2 g t^2 t=sqrt(2h/g) for info, g is not 10 m/s^2 anywhere on Earth. It is approximately 9.81m/s^2

*October 15, 2016*

**chemistry**

No, not a good answer. Under the prior atomic theory any orbital was allowed, so any energy change was allowed. If any energy change (emission) was allowed, then there would be continous spectrum. But the emission observed was specific discrete wavelength (energies) were given...

*October 15, 2016*

**calculus**

lim (-4.9(t+dt)^2+10(t+dt)+2)/dt = -4.9(t^2+2tdt+dt^2)+10t+10dt+2 +4.9t^2-10t-2) /dt = -4.9 (0t^2 + 0t+2tdt+dt^2+10dt) /dt = -9.8t +10 as the limit of dt>>>zero at t=1, then rate of change=.2 m/s

*October 15, 2016*

**Calculus**

average rate of change= f(3)-f(2) / (3-2)= 1/6-1/2=-1/3

*October 15, 2016*

**Physics**

"with a for (force?) every of". Please translate that for me. I am wondering about friction. Net force=mass*acceleration where Net force=pushing force-friction

*October 15, 2016*

**Physics**

speed u and mouse ? it has been be after? Makes no sense to me.

*October 15, 2016*

**chemistry**

correct

*October 14, 2016*

**Geometry**

xy+yz=xz a+a+8=50 2a=42 a=21 a+8=29

*October 14, 2016*

**Physics**

force of gravity? F=1600/4^2 net force is zero, of course, as he is in orbit.

*October 14, 2016*

**Physics**

force=G*78*55/16 weight= mass*9.8N/kg

*October 14, 2016*

**APPHYSIC**

d=vi*t-4.9t^2

*October 14, 2016*

**physics**

work done by unit=PE and Ke at16m, 5.5m/s work done=mg(16)+1/2 m v^2

*October 14, 2016*

**Physics**

a. work= initial KE work=1/2 m v^2 solve for v

*October 14, 2016*

**physics**

1/2 m v^2=1/2 k x^2 v=sqrt(kx^2/m)

*October 14, 2016*

**History**

greed, moral decay, greed, lack of moral structure, greed, moral decay. And some tribal trivialities, and ethnocentrism with a bit of good old fashioned hatred. But mostly moral decay and greed. http://www.nytimes.com/2012/12/16/sunday-review/congos-never-ending-war.html

*October 14, 2016*

**Math**

What is 3:1

*October 14, 2016*

**Physics**

force*distance=1/2 m v^2 solve for force this assumes there are no energy lost on friction in the barrel

*October 13, 2016*

**chemistry**

http://en.chembase.cn/Server/MolImages/E6/AC/E6AC6386-2341-4C0D-8929-61893C7E5689.png

*October 13, 2016*