Saturday

May 28, 2016
Total # Posts: 26,283

**Science HELP**

Suspect so, like humans and dogs and cats.
*January 14, 2016*

**Math**

sl^2= [(1/2) base]^2 + h^2 so sqrt (36+64) d = sqrt [36 + 25 + 81]
*January 14, 2016*

**No idea**

for distance(scalar) you need a ruler but for displacement(vector) you need a compass and a ruler Force is a vector so we not only need the magnitude but also the direction to do this.
*January 14, 2016*

**math,**

26 + 20 - 17 = 29 35 - 29 = 6 play neither
*January 14, 2016*

**Math**

2 w + 2 L = 154 L = 55 so 2 w + 110 = 154 2 w = 44 w = 22
*January 14, 2016*

**science**

If in SERIES the SAME CURRENT passes through all three and the voltages add up to the battery voltage. 10 i + 8 i + 5 i = V or 23 i = V i = V/23
*January 14, 2016*

**Civics**

Read Bill of RIGHTS
*January 14, 2016*

**chemistry**

4.5/13.9 = .323 not 3.32 x = Xo (1/2)^n log (x/Xo) = n log .5 = .323(-.301) = -.09723 x/Xo = 10^-.09723 = .799
*January 14, 2016*

**physics**

same magnetic field through each coil so voltage is in the ratio of the number of turns secondary/primary 60/120 = 1/2
*January 14, 2016*

**Science**

orbital motion is key, merry-go-round
*January 14, 2016*

**Science**

matter moves in accordance with Newton's laws (momentum is conserved, force is rate of change of momentum, action causes equal and opposite reaction) heat moves from hot to cold Electro magnetic energy follows Maxwell's equations.
*January 14, 2016*

**Science**

polar bears have long fur
*January 14, 2016*

**Science**

No,seeing as how I live beside the Gulf of Maine, it is increased flooding that worries me most immediately.
*January 14, 2016*

**math**

area of square = 32.5-7.5 = 25 so it is 5 by 5 = 25 like s = 5
*January 14, 2016*

**Physics**

4*10^-6 C*1 electron/(1.6*10^-19C) = (4/1.6) 10^13 electrons
*January 14, 2016*

**math**

4*8 = 32 3 * 32 = 96 ft^2
*January 14, 2016*

**math**

I see no picture so have no idea what your angles are.
*January 13, 2016*

**Civics**

Here in Massachusetts there are both state and local police forces so I suppose that is the right answer. However both the state and local governments provide funds for building schools. Here at present the state provides half and the city provides half the cost.
*January 13, 2016*

**Physics - equal and opposite**

Google Newton's Third Law.
*January 13, 2016*

**PHYSICS**

v at top = 0 v at two seconds down = Vi 0 = Vi - g t so Vi = 9.81 * 2 average speed during those two seconds is Vaverage = (0 + 2*9.81) /2 so average speed = g = 9.81 9.81 m/s * 2 s = 19.6 meters By the way that was quite a throw :)
*January 13, 2016*

**Physics**

v = Vi + a t stops so 0 = Vi + a (2.8) and -2500 = m a = 1350 a a = -1.85 m/s^2 0 = Vi - 1.85*2.8 Vi = 5.19 m/s
*January 13, 2016*

**Geometry**

same as the angle from the horizon to the top of the lighthouse from the ship tan T = 50/750 T = 3.81 degrees
*January 13, 2016*

**SIERRA**

watch your signs east defined as + initial v = +4.5 final v = -1.5 we want final - initial or (-1.5 - 4.5) impulse = change in momentum 90 (-1.5 - 4.5) = -90(6) = -540 kg m/s or 540 west F = rate of change of momentum = -540/1.2 = - 450 N or 450 N west
*January 13, 2016*

**Physics**

8.2 UP and .5(9.81 ) down = 3.295 Newtons up Work done =Force * 1.5 meters = 3.295*1.5 = 4.9425 Joules so (1/2) (.5) v^2 = 4.9425 v = 4.45 m/s
*January 13, 2016*

**Been there - done that**

http://www.jiskha.com/display.cgi?id=1452713165
*January 13, 2016*

**Civics**

http://worldpopulationreview.com/states/nevada-population/
*January 13, 2016*

**civics**

My son borrowed my chain saw :(
*January 13, 2016*

**Math Help!**

If the forces are in the same direction they add, yes
*January 13, 2016*

**Math**

yes yes
*January 13, 2016*

**Maths**

yes, yes
*January 13, 2016*

**16 no**

NOT MORE </= 30 You knew that
*January 13, 2016*

**biology**

all different acts of the same screen play. I do not think you should have a comma between continental and drift :)
*January 13, 2016*

**math**

volume = dimension^3 to double volume multiply dimensions by 2^(1/3) = 1.26 so 2.52 * 3.78 * 5.04 ================== check: 2*3*4 = 24 2.52 * 3.78 * 5.04 = 48.006 close enough to 48 :)
*January 13, 2016*

**Math**

do #7 more carefully
*January 13, 2016*

**Math**

5.5.4 + 0.2x =-1.4x + 8.6 2 --2 .2*** 20 ======================== 1.6 x = 3.2 16 x = 32 x = 2 I get
*January 13, 2016*

**PHYSICS**

a = change in v / change in t t1 = 1 Y1 = 2 V1 = 2 Dv = 2 t2 = 2 Y2 = 6 V2 = 4 Dv = 2 t3 = 3 Y3 = 12V3 = 6 Dv = 2 change in V = 2/1 = 2 m/s^2
*January 13, 2016*

**Physics**

fb = frequency heard then emmitted by blood particle fb = (c+v) f /c fl = frequency heard back at the source f receiver = fr = fb c/(c-v) so the result is: fr = f * (c+v)/(c-v) which is B (sort of, parenthesis missing)
*January 13, 2016*

**Physics**

You are welcome.
*January 13, 2016*

**Physics**

LOL, figured you knew how to do all that initial bullet speed = V that is what we want we know final speed is 4.7 conservation of momentum: .15 V = (.15+1.85)(4.7)
*January 13, 2016*

**Physics**

at the top of the circle: v^2/r = g v^2 = g r = 9.81 * .45 = 4.4145 so at top v = 2.1 m/s so Kinetic energy at the bottom must be enough to get up there at that speed (1/2) m v^2 = m g h + (1/2) m (4.4145) (1/2) v^2 = 9.81(0.90) + 2.207 v = 4.7 m/s at bottom after crash NOW do...
*January 13, 2016*

**SCIENCEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE**

23. The number of protons in the nucleus of an atom is its ___. (1 point) ============================= HEY - I am happy to help a student who is stuck on something but I will not do your work for you. If you even read this question before posting it you would have answered ...
*January 13, 2016*

**physics**

F = M A = 1500 * 10 = 15,000 NEWTONS
*January 13, 2016*

**Physics**

17 min = 1020 seconds coulomb = amps * seconds so coulombs = .526 etc * 1020 or about 536 coulombs so answer = (536 / 1.602) 10^19
*January 13, 2016*

**chemistry**

(1/2)^ 6 = 1/64 so we are talking six half lives for A is 12 hours so one half life for A is 2 hours Now I will read the problem :) well half life of B is 3 hours 1/32 = 5 half lives 5 * 3 = 15 hours Not hard, just keep your wits about you and think ! (and check my arithmetic :)
*January 13, 2016*

**physics**

define + is up Draw a picture x = 0 at A , Fa up x = 80 at C , Fc up x = 50 at CG, mg =4*9.81=39.24 down so Fcg = -39.24 N sum of forces = 0 Fa + Fc + Fcg = 0 so Fa+Fc = 39.24 N now do moments about 0 for example Fc * 80 = 39.24 * 50 Fc = 24.5 N so Fa = 39.24 - 24.5 = 14.7 N
*January 13, 2016*

**chemistry**

Oh my. How many electrons? Nickel is 58.7 grams per mole or 6*10^23 atoms which here is 6*10^23 electros so 6 g * 6.022*10^23 electrons/58.7 g = .6155 * 10^23 electrons 1.602*10^-19 coulomb/electron so the product is .986 * 10^4 Coulombs a coulomb is an amp second so .986*10^4...
*January 13, 2016*

**physics**

.3 * 55 * 9.81
*January 13, 2016*

**Algebra**

3 x + 2 y = 13.5 2 x + 1 y = 8 =================== 3 x + 2 y = 13.5 4 x + 2 y = 16 -----------------subtract - x = - 2.5 x = 2.50 for hot dog (A yes) then 5 + y = 8 y = 3.00 for soda (B no ) C yes, that is what I did D makes no sense at all
*January 13, 2016*

**Math Help!**

1 A yes 2.yes 6/11 = 84/x 6 x = 11 * 84 x = 11*14 = 154
*January 13, 2016*

**Math Help!**

well I will do the last one 22/55 = 12/h multiply both sides by the LCD which is 55 h then (22/55) (55 h ) = (12/h)(55 h) or 22 h = 12 * 55 divide both sides by 11 2 h = 12 * 5 divide both sides by 2 h = 6 * 5 h = 30 ------------------- I have gone step by step to show you why...
*January 13, 2016*

**Algebra 1**

.793 is not very good, like at least above .8 but it is not bad and it might show that you are on the right track.
*January 13, 2016*

**algebra**

(1 branch/2 inches )72 inches = 36 branches
*January 13, 2016*

**physics**

d = (1/2) a t^2 100 = (1/2) a (100) so a = 2 m/s^2 F = m a = 32.5*2 = 65 N
*January 13, 2016*

**Huh?**

You bought one apple and sold ten? suspect you bought each at 10 and sold each at 11 1/10 = 0.1 0.1 * 100 = 10%
*January 13, 2016*

**Physics **

dv/dt = -6 t^3 v = -(6/4)t^4 + 5 when it stops, v = 0 t^4 = 3.333 seconds to stop t = 1.351 and t^5 = 4.504 x = -(6/20) t^5 + 5 t x = -(6/20)(4.504) + 6.755 = -1.3512 + 6.755 = 5.4 meters
*January 13, 2016*

**Chemistry**

heat to warm copper= Ccopper * 50 *(39.3-10) heat to cool water= 4.18 * 200 * (40-39.3) set them equal and solve for Ccopper
*January 13, 2016*

**Physics**

radius = Rearth cos 41.9 omega =2 pi/(24 hrs * 1 hr/3600 s) v = r omega
*January 13, 2016*

**Math**

9. percent equivalent to 3 is... Is it 0.03%? No 3 * 100 = 300 percent
*January 13, 2016*

**Math NO !**

Oh, is 4 1/4 as a percent - 4.25%? 4.25 * 100 = 425 % More than 4 times is more than 400 percent more: 4. fraction equivalent to 0.75% is... Is it 3/4? NO!!! .75/100 = .0075
*January 13, 2016*

**math**

for the same numerator the bigger the bottom, the smaller the result surely 1/4 is less than 1/2 :)
*January 12, 2016*

**Physics**

think lifting a barbell work in = Force up * distance up That is also the increase on potential energy m g h when you drop it that same value in Joules becomes (1/2) m v^2
*January 12, 2016*

**Physics**

Conservation of energy work done = increase of energy or work done = increase in kinetic energy + increase on potential energy
*January 12, 2016*

**Math**

photo area = 88 in^2 outside dimension = 8+2x by 11+2x so we want (2x+8)(2x+11) - 88 = 42 4 x^2 + 38 x - 42 = 0 2 x^2 + 19 x - 21 = 0 (2x + 21)(x-1) = 0 x = 1 inch
*January 12, 2016*

**Math**

LOL check your physics question
*January 12, 2016*

**Math**

silver back got 1 and 2 however 3 when you multiply by negative, you reverse the arrow 3. -5 p > - 30 5 p < 30 p < 6 which is b
*January 12, 2016*

**Physics**

F cos 38 = m a easy way is for constant acceleration v average = (Vi+Vf)/2 so v average = (0 + 2.2)/2 = 1.1 m/s so time = t = 3.4/1.1 = 3.09 s a = change in v / time = 2.2 / 3.09 = .712 m/s^2 so F cos 38 = 12 * .712 F = 10.8 Newtons
*January 12, 2016*

**Math**

3 (3 + 7/8) = 9 + 21/8 =11 5/8 15 4/8 - 11 5/8 = 14 12/8 - 11 5/8 = 3 7/8 He could get one more if it were not for the saw cerfs :) ------------------ check note 3 7/8 = 4 - 1/8 4 (4-1/8) = 16 - 4/8 = 15 1/2 sure enough
*January 12, 2016*

**Math**

1.12 = 8 x x = .14 or 14 % extra
*January 12, 2016*

**Math**

yes
*January 12, 2016*

**math**

2 v + 3 (v-10) = 220 5 v - 30 = 220 5 v = 250 v = 50
*January 12, 2016*

**Math (Calculus - Limits)**

(x-8)(x+b) = x^2 + 2 x + c - 8 b = c and -8 x + b x = 2 x or b = 10 so c = -80
*January 12, 2016*

**Math**

I mean 30 + 12 + 30 + 12
*January 12, 2016*

**Math**

so 20 + 12 + 30 + 12 :)
*January 12, 2016*

**Math**

1.6 x x + .6 x I guess :)
*January 12, 2016*

**Physics help**

loss of potential energy = gain in kinetic energy from 38.7 to 25.6: m g (38.7 - 25.6) = (1/2) m v^2 v = sqrt (2 * 9.81 * 13.1) = 16 m/s 12 = sqrt (2 * 9.81 * distance down) 144 = 19.62 d d = 7.34 distance of fall so 38.7 - 7.34 = 31.3 meters high at 12 m/s v = sqrt (2 *9.81* ...
*January 12, 2016*

**physics**

m = F/a = 48/3 = 16 kg
*January 12, 2016*

**physics**

both horizontal and down are 10 * sqrt2 /2 Newtons because sin 45 = cos 45 = sqrt2 /2
*January 12, 2016*

**Math**

xx 1 2 3 4 5 6 ------------- 1| 1 2 3 4 5 6 2| 2 4 6 8 10 12 3| 3 6 9 12 15 18 4| 4 8 12 16 20 24 5| 5 10 15 20 25 30 6| 6 12 18 24 30 36 well Leah's number must happen 3 times for every 2 of Sam's for example 2 happens twice (Sam) 4 happens 3 times (Leah) is there a ...
*January 12, 2016*

**math**

radius pond = 13 yds radius outside walk = 13+2 = 15 yds area of walk = pi (15^2-13^2) Got it now ?
*January 12, 2016*

**math help please**

5 (36-15)
*January 12, 2016*

**Algebra**

m + (m-15) = 44 ?? 2 m = 59 m = 29.5 s = m-15 = 14.5
*January 12, 2016*

**math help please**

20 + 5 + 20 + 5
*January 12, 2016*

**physics**

LOL - I guess unless the string breaks they better have the same acceleration force of m1 down slope = 3.7 g sin 30 = 1.85 g force of m2 the other way = 2.3 g net force = (2.3 -1.85)g = .45 * 9.81 = 4.41 N block 2 wins and heads straight down, block 1 heads up slope a = 4.41...
*January 12, 2016*

**Algebra II**

well, I suppose I would check -125^4/3 -125^1/3 = -5 then(-5)^4 = 625 so it looks like you are right to me
*January 12, 2016*

**Calculus AB**

Ah, so you have heard the words "mean value theorem" now let's see what the slope is from x = 1 to x = 2 y(2) = |(-2)(6)| = 12 y(1) = |(-5)(3)| = 15 so slope = -3/1 = -3 Mean value theorem says slope must be 3 at least once between = 1 and x = 2 lets look at ...
*January 12, 2016*

**Calculus AB**

Here you go http://www.sosmath.com/calculus/diff/der11/der11.html (mean value theorem)
*January 12, 2016*

**Calculus AB**

DRAW A GRAPH !!! somehow a smooth curve has to get from 4 at -3 back to 4 at +4 It could be a horizontal line, but that is a trivial case It could start up, but then would have to come down. SO HAS TO HAVE SLOPE of ZERO in here at least once if it started down, it has to come ...
*January 12, 2016*

**us history. Plz help!**

Well where is Louisiana and the Mississippi valley on your map ?
*January 12, 2016*

**us history. Plz help!**

3 is wrong. The United States did not exist when France was fighting England and us in the north east. I suspect they mean Louisiana purchase 5 wrong remember slavery etc at the time period 7 - I do not remember, assume you are right 9 I guess 11 no 12 - need for strong ...
*January 12, 2016*

**math help**

45 min + 30 min = 75 min = 1 hour and 15 min = 1.25 hr 9 - 1.25 = 7.75 which is 7:45 am
*January 12, 2016*

**Math**

2.5 gal (4 qt/gal) = 10 qt
*January 12, 2016*

**math help**

70/2
*January 12, 2016*

**math**

3 * 5.5 = 16.5 = 17
*January 12, 2016*

**math**

if n is 12 then n+6 is 18
*January 12, 2016*

**Conversion**

if it is 10 seconds I suspect 110 yards :) 1760 yd/mi 3600 s/h 110 yd/10 s (1 mi/1760 yd)(3600s/h) = 22.3 mi/h
*January 12, 2016*

**PHYSICS 1**

if your angles are math convention, counterclockwise from x axis and not compass angles from north then just use what Steve gave you for A Ax = 145 cos 190 Ay = 145 sin 190 etc
*January 12, 2016*

**math**

4.5 / 60
*January 12, 2016*

**6 is right**

You got one, enough already
*January 12, 2016*

**Random selections?**

4 C Hey have you just picked random answers?
*January 12, 2016*

**Math**

3D wrong, solution is y = 0 but what about 0 x = 0 in 2C ?
*January 12, 2016*