Tuesday

July 29, 2014

July 29, 2014

Total # Posts: 17,556

**US Government**

The answer is in the link Ms. Sue gave you.

**Alegbra**

It is very difficult to fit a line to one point.

**Alegbra**

both sides are 0 at (6,-8) then y goes down 5 times as fast as x goes up check: from that point go right 1 and down 5 (7, -13) is that on the line? -13 + 8 = ???? -5 (7-6) -5 = -5(1) sure enough

**engr240**

I have no idea. Is this part of an equation? Should it be equal to zero or something?

**Alegbra**

y = m x + b 7 = 0 + b b = 7 so y = -6 x + 7 where does that hit x axis ? 0 = -6 x + 7 x = 7/6 so (7/6 , 0) draw line through (7/6 , 0) and (0 , 7)

**Geometry**

2 pi r = 2 pi (2x) = 4 pi x

**Physics mit 2.01x**

No (former MIT professor), I do not do MITx problems in Course 8 or Course 2. You are on your own. The 8.01x crowd swamped this board the last time around.

**science**

pi r^2 h pi 1*1*12 = 12 pi cm^3 or cc = 37.7 cubic centimeters

**physics**

a) Huh? at x = 0 and t = 0 , y = 0 so the phase constant is 0 b) at x = .0229 m and t = .197 .745(.0229) - 42.9(.197) = -8.434 radians = -482 degrees which is -360 - 123 degrees

**physics**

well, first do the vertical problem, the ball how long does it take to fall 20 m? 20 = (1/2) (10) t^2 t^2 = 4 t = 2 seconds so it will take to seconds to fall. By symmetry it will also take 2 seconds to rise and hit the plane how fast is it going when it hits the ground? u = a...

**physics**

by the way part B is also the average speed times the time x = 5.25 * 5.2

**physics**

a = change in velocity / change in time = ( 0 - 10.5) / 5.2 m/s^2 x = (1/2) a t^2 = (1/2) * a from above * (5.2) * (5.2)

**SCI 207**

I suppose those are the people with expensive houses on the shore. However what is meant by "worst impacts"? If it means losing the most money it may be correct. However wealthy people probably can survive the loss of shore side property without ending up homeless. T...

**physics**

To go from km/h to m/s divide by 3.6 which is 1000 m/km / 3600 s/min a = change in velocity/time (note it is negative) F = m a By the way, this ignores wave resistance which would be a major part of the retarding force.

**chemistry**

P1 V1 = P2 V2 so V2 = P1 V1/P2 I am assuming that these are total pressures and no "gage" pressures. If they are gage pressures add 1 atm to both P1 and P2

**physics**

well, I guess it is ok to use g = 9.81 m/s^2 but we will have to check later if the thing is a significant fraction of an earth radius high. (1/2) m v^2 = m g h v^2 = 2 g h h = v^2/19.6 = 49*10^4 / 19.6 = 25,000 meters that is a small fraction of earth radius so constant g ass...

**Physics**

Look below

**Physics**

If I have this picture right block one on the incline is pulling block two on the level above toward the incline. There is one force pulling block one down the incline and string tension T holding it back Fpull = 4.4 g sin 30 = 2.2 g 2.2 g - T = mu * 4.4 g cos 30 I assume that...

**Physics**

1 g/cm^3*1kg/1000 g* 100*100*100 cm^3/m^3 = 1000 kg/m^3 you know this anyway because the density of fresh water is about 1 g/cc or 1000kg/m^3

**Math 221**

well, if it ends in 0 or 5, divide by 5 26 / 21 that is 13*2/7*3 so there is nothing more to be cancelled.

**American Government**

This is not my field but one thought crosses my mind immediately. It is in the interest of each state to have as few welfare recipients as possible. Therefore each state would feel pressure to provide as little help as possible hoping that the people will decide to move to ano...

**Science**

If you do A and the bread gets moldy with no air, then the mold spores probably did not come from the air.

**Science**

Graph that P V 8 1 4 2 2 4 1 8 Every time you cut the volume in half you double the pressure P V = k = 8 so P = 8/V so yes, confirmed

**math**

a bit over ten gallons a week at about three dollars per gallon = $30

**math**

out of every seven candies 5 are red and 2 are green so out of 5*7 = 35 candies 5*5 = 25 are red and 5*2 = 10 are green B.

**physics**

vertical problem (time and speed same as 104 meter fall): v = Vi - 9.81 t 0 = Vi - 9.81 t t = Vi/9.81 104 = (1/2) g t^2 104 = (1/2) (9.81)(Vi^2/9.81^2) Vi^ = 2 * 9.81 * 104 Vi = 45.2 m/s horizontal problem (constant speed) t = Vi/9.81 = 4.61 seconds u = 53/4.61 = 11.5 m/s tan ...

**physic**

Because I believe that is the correct value for radius of the earth.

**physic**

for earth for example F = G M1 M2 /r^2 = (6.67*10^-11)(5.98*10^24)(67.5)/ (6.38*10^6 )^2 = 66.14 * 10^ 1 = 661 Newtons that better be pretty close to m g or 67.5*9.81 = 662 Newtons

**physic**

F = G M1 M2 / d^2 where G = 6.67*10-11 N m^2/kg^2 I think you mean radius for distance radius of earth = 6.38*10^6 meters

**Physics**

Hey look. I showed you how to do it for the earth mass and man mass. Do the same for the two balls .3 m apart. G * .3 *.3 / 3^2 = G

**Physics**

This is the same as your problem above with the different planets and the weight of the man on each.

**Physics**

same as problem above

**physic**

1609/4.740 and 1609/4.695

**physic**

x = 6 t + (1/2)(2) t^2 = 6(8) + 64 = 112 meters

**history**

import duties ?

**Math**

total area of patio = 240 area of garden = x^2 useable patio area = 12 - x^2 if x is more than 12, you can not walk around the garden

**physics**

better get a CD and try it :)

**physics**

ok, well if I have it right the pin is at the edge of the hole, 0.75 cm above the center of gravity of the CD for a small angle A the restoring moment about that pin is -m g (.0075)sin A = -.0075 m g A = -.0075*.017*9.81 A = -.00125 A the moment of inertia of the CD about its ...

**physics**

sorry, I need a picture.

**physics**

By the way magnetic field lines usually are draw going from N to S OUTSIDE the magnet.

**physics**

1. How would they cross? 2. different constants/r^2 k Q1 Q2/r^2 versus G M1 M2/r^2 see https://www.google.com/search?q=exponential+field+definition&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a&channel=sb#channel=sb&q=exponential+function+definition&re...

**whoops**

14.4 *10^-9 = 1.44 *10^-8

**physics**

k Q/r 9*10^9 * 1.6*10^-19/10^-1 14.4 *10^-9 = 1.44 *10^-10

**algebraic expression**

I don't know.

**physics**

yes, looking for ratio of charge to mass, knowing mass, could calculate charge (slight oversimplification) see: http://ffden-2.phys.uaf.edu/212_fall2003.web.dir/Ryan_McAllister/Slide3.htm

**physics**

potential energy of mass m at surface = -GMmoon m/r = - m (6.67*10^-11) (7.35*10^22) /(1.74*10^6) = m (28.2*10^5) Needs that many Joules of Ke so (1/2) m v^2 = 2.82*10^6 m v^2 = 5.64 *10^6 v = 2.37*10^3 = 2370 m/s by the way: http://www.1728.org/escvel.htm

**physics**

You are welcome.

**physics**

E = 9*10^9 Q/r^2 here Q = 1.6*10^-19 so 9*10^-3 = 9*10^9 (1.6*10^-19)/r^2 r^2 = 1.6 * 10^-7 = 16 * 10^-8 r = 4*10^-4 meters = .4 millimeters

**Math**

using that regression line calculator y = -4.29x + 28.3 (2.5, 17.6)

**Math**

http://www.alcula.com/calculators/statistics/linear-regression/

**Math**

same as above. enough already.

**Math**

It would take you less time to do these problems than to post them.

**Math**

Your problems are all answered by the link I gave you.

**Math**

tan(90-39) = AP/40 so AP = 49.4 tan (90-52) = BQ/40 so BQ = 31.2 so P is (49.4-31.2) or 18.1 km south of Q and 40 km west of q tan theta = 40/18.1 theta = 65.7 degrees east of north from P to Q

**Math**

http://davidmlane.com/hyperstat/z_table.html

**Math**

The link I gave you does all of these. In fact if you have a normal table handy, all your questions are really answered in it.

**Math**

Use link below for normal curve: http://davidmlane.com/hyperstat/z_table.html

**Math**

http://davidmlane.com/hyperstat/z_table.html

**Math**

122 z = (122-182)/30 = -2 242 z = (242 - 182)/30 = +2 then use normal table or use: for example http://davidmlane.com/hyperstat/z_table.html result .9545 in that range so .9545*600 = 573

**Math**

http://davidmlane.com/hyperstat/z_table.html

**Dynamics**

d^2x/dt^2 = 2 t - 1 dx/dt = t^2 - t + c at t = 0, dx/dt = 2 so c = 2 so v = dx/dt = t^2 - t + 2 x = (1/3) t^3 - (1/2) t^2 + 2 t + c when t = 0 x = a so c = 1 x = (1/3) t^3 - (1/2) t^2 + 2 t + 1 so at t = 6 v = 36 -6 + 2 = 32 m/s and x = 67 total distance = 67-1 = 66 assuming x...

**Hunting training**

So would I (but I know nothing about this really)

**Hunting training**

I agree because my spaniel won't hunt.

**PHYSICS**

at ten meters it has dropped 15 meters (1/2) m v^2 = m g h v^2 = 2 * 9.81 * 15 = 294.3 v = 17.2 m/s at 10 m above ground d = (1/2) g t^2 25 = 4.9 t^2 t = 2.26 seconds

**science**

walk north until the arrow flips :)

**science**

...... but not found yet

**science**

The magnetic monopole is a much sought after object :)

**science**

http://cosmoquest.org/forum/showthread.php?91956-The-Moon-Specular-and-Diffuse-Reflection

**science**

It is called reverberation. See: http://www.wisegeek.com/what-is-a-reverberation.htm#didyouknowout

**Math**

You are welcome.

**Math**

to fit in the box the radius of a round pizza must be less than or equal to 6 inches A = 3.14159 * r^2 = 3.14159 * 36

**PHYSICS**

F * 100 / 80 = 200

**chemistry step by step for me clearly**

sorry 3 * 6 = 18 mols

**chemistry step by step for me clearly**

I have to assume you mean 2.684 grams of Al2(SO4)3 and water per cc. One of those grams is water so we have 1.684 grams of Al2(SO4)3 in every cc Al2(s04)3 How many grams per mol? 2 Al = 2 * 27 = 54 3 S = 3 * 32 = 12 O = 12 * 16 = 192 so Al2 (SO3)4 = 278 grams/mol If we have 1....

**Physics**

How fast can the stack accelerate without the books above the first one slipping? weight down on bottom book = 5 * 4 kg * g maximum static friction force between top 5 and bottom book = 5 * 4 * g * 0.3 so max force = mass of top 5 * a 5*4*g*.3 = 5*4 * a so a = .3 g that gives ...

**electric circuit**

Interesting, went nameless :)

**Trigonometry**

A(of L and w) = L * w if w = 1 then A(L) = L

**stats**

57.21% or .5721

**stats**

I think the same as the probability that one is more than 2.90 mean = 3 we are at .1 below mean Z = -.1/.55 = -.18 from normal table if Z = -.18 then F(z) about .421 so about 42% are below so about 58 % are above 2.9 For accurate table use http://davidmlane.com/hyperstat/z_tab...

**error**

arithmetic! (10*9*8)/(16*15*14) = .2143 1 - .2143 = .7857

**Math**

p = probability defective = 6/16 = .375 1 - p = 10/16 = .625 = probability good we do three trials on the box. They all must be good if it is to pass probability of first trial fuse good = 10/16 probability of second choice being good fuse = 9/15 third = 8/14 so probability of...

**No picture**

If you tried to copy and paste, that does not work here.

**US Government**

However in real life they seem to be closer to: http://www.constitutionparty.com/our-principles/key-issues/

**US Government**

http://www.modernwhig.org/handbook/who-are-modern-whigs/what-we-believe I suspect Republicans like to think they share these principles.

**PHI 208 Week 4 Reading Quiz**

Hard to tell.

**Physics**

F = q E = m a so a = (q/m)E = (1.6*10^-19/1.67*10^-27)5*10^2 = 4.79 * 10^10 m/s^2 v = a t 3.5*10^4 = 4.79 * 10^10 t t = .731 * 10^-6 = 7.31*10^-7 seconds d = (1/2) a t^2 Ke = (1/2) m v^2 I think you can do c and d

**US Government**

http://www.fec.gov/ans/answers_pac.shtml

**physics**

There is indeed a magnetic dipole which has field lines of the same shape as an electric charge dipole. We also use the dipole model in fluid physics combining a source and a sink close together which also has the same sort of streamlines. All are examples of moments, meaning ...

**math**

Here is a picture of a similar (no pun intended) problem http://mathforum.org/sanders/connectinggeometry/ch_09Similar.html

**math**

No hypotenuse is necessary. We are looking at corresponding sides of similar triangles here 3/4 = h/20 so 4 h = 4 * 5 *3 h = 15

**Statistics/Probability**

http://davidmlane.com/hyperstat/z_table.html

**algebra2**

You are making as mountain out of a mole hill: 2x + 4 = 3x - 12

**Physics- help please**

q is the electron charge -1.6*10^-19 Coulombs You are supposed to know that, The charge on a proton is equal and opposite in sign.

**Physics**

v (t+2) = (1/2) a t^2

**math**

y = (3/5) x + b -4 = (3/5)(2) + b b = -20/5 - 6/5 = -26/5 y = (3/5) x - 26/5 5 y = 3 x - 26

**math**

m = (-5 - 1)/(2-4) = 3 m' = -1/m = -1/3 y = -x/3 + b find point on original line halfway between x = (4 +2 )/2 = 3 y = (1 - 5)/2 = -2 so -2 = -3/3 + b b = -1 so y = -x/3 - 1 3 y = -x - 3

**business**

8%/4 = 2% per quarter so every three months multiply by 1.02 25 * 1.02^n = 45 1.02^n = 1.8 n log 1.02 = log 1.8 n = 29.68 quarters or 7.42 years

**Urgent Calculus Help 2**

You are welcome.

**Urgent Calculus Help 2**

dy/dx = 6x d/dx [ln(x+4)]+ 6 ln(x+4) = 6 x /(x+4) + 6 ln(x+4) so at x = 2 dy/dx = slope = m = 12/ln(6) + 6 ln (6) but ln (6) = 1.79 so use that to find the slope m then we have y = m x + b and we know m find y at x = 2 y= 12 (1.79) = 21.5 so use that 21.5 = 2 m + b we know m, ...

**Urgent Calculus Help**

h' = df/dg * dg/dx at x = 2 dg/dx = -2 and g = 7 df/dg at g = 7 = -8 so -8 * -2 = + 16 that is how, you do the next

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