Friday
March 6, 2015

Posts by henry


Total # Posts: 10,191

Chemistry
The primary route for making copper iodide is by reacting potassium iodide with copper sulfate: 2CuSO4 + 4KI + 2Na2S2O3 ==> 2CuI + 2K2SO4 + 2NaI + Na2S4O6 Identify potential green chemistry and green engineering challenges of the reaction.
February 1, 2015

Physics
Dc = Dp 0.5a*t^2 = 8.93 * 2.88 0.5a*2.88^2 = 25.72 Solve for a.
January 30, 2015

Physics
V = 43.3 m/s. a = -5.61 m/s^2 d = 24 + 55.9 = 79.9 m. V^2 = Vo^2 + 2a*d = 43.3^2 Vo^2 - 11.22*79.9 = 1874.9 Vo^2 = 1874.9 + 21036 = 22,911 Vo = 151.4 m/s. = Initial velocity. V = Vo + a*t V = 43.3 m/s. Vo = 151.4 m/s. a = -5.61 m/s^2 Solve for t.
January 30, 2015

Physics
V^2 = Vo^2 + 2a*d V = 333 m/s. Vo = 370 m/s. d = 12 cm = 0.12 m. Solve for a. It will be negative.
January 30, 2015

physics
h = Vo*t + 0.5g*t^2 = 1.5 m. Vo*0.18 + 4.9*0.18^2 = 1.5 0.18Vo + 0.159 = 1.5 0.18Vo = 1.5 - 0.159 = 1.34 Vo = 7.45 m/s = Initial velocity at top of window. V^2 = Vo^2 + 2g*h = 7.45^2 0 + 19.6*h = 55.5 h = 2.83 m. Above the window.
January 30, 2015

Green Chemistry
The primary route for making copper iodide is by reacting potassium iodide with copper sulfate: 2CuSO4 + 4KI + 2Na2S2O3 ==> 2CuI + 2K2SO4 + 2NaI + Na2S4O6 Identify potential green chemistry and green engineering challenges of the reaction.
January 30, 2015

physics
V^2 = Vo^2 + 2a*d V = 0 Vo = 125 m/s a = -9.8 m/s^2 Solve for d, the length.
January 30, 2015

physics
0.5g*t^2 = 2 4.9t^2 = 2 t^2 = 0.408 Tf = 0.639 s. = Fall time. Tr = Tf = 0.639 s. = Rise time. Tr+Tf = 0.639 + 0.639 = 1.28 s. = Time in air.
January 29, 2015

physics
M*g = 74.6kg * 9.8N/kg = 731.1 N. = Wt. of the skier. Fp = 731.1*sin39.0 = 460.1 N. = Force parallel to the incline. Work = Fp*d = 460.1 * 63.3 = 29,124 J.
January 29, 2015

Physic
V^2 = Vo^2 + 2g*h V = 0 Vo = 78.5 m/s. g = -9.8 m/s^2. Solve for h.
January 29, 2015

Physics
Circumference = pi*Dia. = 3.14 * 50 = 157.1 cm. 25rad * 1rev/6.28rad = 3.98 revs. d = 157.1cm/rev * 3.98revs = 625.4 cm.
January 29, 2015

Need Help Physics
Vbc = Vb + Vc = 6.44i Vb + 1.09 = 6.44i Vb = -1.09 + 6.44i Tan Ar = Y/X = 6.44/-1.09 = -5.90826 Ar = -80.4o = Reference angle. A = -80.4 + 180 = 99.6o, CCW = 9.6o W. of N.
January 29, 2015

Maths
PQ = X1 = 15 m. X2 = hor. distance from Q to kite. Tan45 = h/X2 h = X2*Tan45 Tan35 = h/(X1+X2) h = (X1+X2)*Tan35 = (15+X2)*Tan35 X2*Tan45 = (15+X2)*Tan35 X2 = 10.5 + 0.7X2 0.3X2 = 10.5 X2 = 35 m. h = X2*Tan45 = 35 * Tan45 = 35 m. h = (X1+X2)*Tan35 = 50*Tan35 = 35 m.
January 29, 2015

physics
e. None of the above.
January 29, 2015

physics
d = Vo*t + (-Vo^2/2a) = 25*0.564 + -(25^2)/-8 = 92.2 m.
January 29, 2015

physicss
V = Vo + a*t = -52 m/s 44 + a*0.003 = -52 0.003a = -52 - 44 = -96 a = -0.032 m/s^2 F = M*a
January 29, 2015

physics
a. Vo = 25m/s[35o] Xo = 25*Cos35 = Yo = 25*sin35 = b. See previous prob. c. See previous prob.
January 29, 2015

physics
Vo = 20m/s[30o] Xo = 20*Cos30 = 17.3 m/s. Yo = 20*sin30 = 10 m/s. Y = Yo + g*Tr Y = 0 Yo = 10 m/s. g = -9.8 m/s^2 Solve for Tr(Rise time). Tf = Tr = Fall time. Dx = Xo * (Tr+Tf)
January 29, 2015

physics
h = 0.5g*t^2 h = 1.40 m g = +9.8 m/s^2 Solve for t(Fall time). Xo = 0.600 m/s Dx = Xo * t
January 29, 2015

physics
Mass = 5.0L * 1oz/0.03L * 0.454kg/16oz = 4.73 kg.
January 28, 2015

Physics
V = 115km/h = 115000m/3600s = 31.94 m/s. Momentum = m*V Direction: East.
January 28, 2015

physics
d = V*t = 8 miles (Vs-Vc)t = 8 Vs = 1.7 m/h Vc = 0.7 m/h Solve for t.
January 28, 2015

physics
V = Vo + a*t V = 0 Vo = 8.2 m/s t = 5.8 s. Solve for a (It will be negative). F = m*a
January 28, 2015

Physics
V^2 = Vo^2 + 2g*h V = 0 Vo = 78.5 m/s. g = -9.8m/s^2 Solve for h.
January 27, 2015

Physics
h = 15 m Xo = 478 m/s? = Initial hor. speed. h = 0.5g*t^2 = 15 m 4.9t^2 = 15 t^2 = 3.06 Tf = 1.75 s.Fall time. Dx = Xo*Tf = 478m/s * 1.75s = 836 m. From bottom of cliff.
January 25, 2015

physics
V = 11.5m/s[236o] - 6.7m/s[270o] V = 11.5*Cos236 + 11.5*sin236 - (-6.7i) = -6.43 - 9.53i + 6.7i = -6.43 - 2.83i Tan Ar = Y/X = -2.83/-6.43 = 0.44074 Ar = 23.8o = Reference angle. A = 23.8 + 180 = 203.8o, CCW = 66.2o W. of S. = Direction. V = X/Cos2o3.8 = -6.43/-.915 = 7.03 m/s...
January 25, 2015

physics
h = 0.5g*t^2 = 2 m. 4.9t^2 = 2 t^2 = 0.408 Tf = 0.639 s. = Fall time. Xo*Tf = 4.4 m Xo * 0.639 = 4.4 Xo = 6.89 m/s.
January 25, 2015

phys
V = Vo + g*t Vo = 0 g = +9.8 m/s^2 t = 3.5 s. Solve for V.
January 25, 2015

physics
F = 225N/m * 0.15m = 33.75 N.
January 25, 2015

physics
V^2 = Vo^2 + 2a*d = 15^2 37^2 + 2a*0.31 = 15^2 2a*0.31 = 15^2 - 37^2 a = (15^2-37^2)/0.62 = -1845.2 m/s^2 A. V = Vo + a*t t = (V-Vo)/a = (15-37)/-1845.2 = 0.012 s B. V^2 = Vo^2 + 2a*d V = 0 Vo = 37 m/s a = -1845.2 Solve for d(thickness).
January 25, 2015

physics
M1*V1 + M2*V2 = M1*V + M2*0.76 24*60.8 + 12*15.2 = 24*V + 12*0.76. Solve for V(cm/s).
January 25, 2015

physics
M1*V1 + M2*V2 = M1*V + M2*V 2100*12 + 2780*0 = 2100V + 2780V 25,200 = 4880V V = 5.16 m/s. See Related Questions: 10-30-14, 9:40 PM.
January 25, 2015

Physics
When they are acting in the same direction: 5 + 7 = 12 N.
January 25, 2015

Physics
V = 22.6km/18min * 1min/60s = 0.0209 km/s = 20.9 m/s.
January 25, 2015

College Physics
d = V*t = 0.12 m t = 0.12/V = 0.12/7*10^7=1.71*10^-5 s.
January 24, 2015

Physics
Dc = 19t = Distance of the car after t1. Dm = Vo*t + 0.5a*t^2 = Distance of motorcycle after t1. Dm = Dc + 52 Vo*t + 0.5a*t^2 = 19t + 52 19*t + 2.5*t^2 = 19t + 52 19t - 19t + 2.5*t^2 = 52 t^2 = 20.8 t = 4.56 s. So the motorcycle caught-up 4.56 s after it started to accelerate.
January 24, 2015

Physics
V1/V2 = M2/M1 = 56kg/96kg = 0.583
January 24, 2015

science
a. Fx = 3000*Cos30 = 2598 N. b. Fy = 3000*sin30 = 1500 N. = Lifting force.
January 24, 2015

Physics
See previous post: Fri, 1-23-15, 5:42 PM.
January 24, 2015

Physics
V^2 = Vo^2 + 2a*d = 0 Vo^2 = -2a*d = -2*(-7.2)*72 = 1036.8 Vo = 32.2 m/s. = Speed before braking.
January 23, 2015

math
Let g = 10 m/s^2. d = 0.5g*t^2 = 5*9^2 = 405 m.
January 23, 2015

physics
Vo = 50m/s @ A Degrees Xo = 50*Cos A Yo = 50*sin A Y^2 = Yo^2 + 2g*h = 0 @ max ht. Yo^2 = -2g*h = -2*(-9.8)*100 = 1960 Yo = 44.27 m/s = Ver. component of initial velocity. Yo = 50*sin A = 44.27 sin A = 44.27/50 = 0.88544 A = 62.3o. = Angle of projection. Y = Yo + g*Tr = 0 Tr...
January 23, 2015

science
d1 + d2 = 12 m. d1 = Vo*t + 0.5g*t^2 d2 = 0.5g*t^2 16*t - 4.9*t^2 + 4.9*t^2 = 12 16*t = 12 t = 0.75 s.
January 22, 2015

science
a = (V-Vo)/t = 30-0)/10 = 3 m/s^2
January 22, 2015

Physics
P = F * d/t = M*g * d/t = 5*9.8 * 12/15 = 39.2 J/s = 39.2 Watts.
January 22, 2015

physics
Vo[51o] Xo = 7 m/s Vo = ? Xo = Vo*Cos51 = 7 m/s Vo = 7/Cos51 = 11.12 m/s = Initial velocity. Yo = Vo*sin51 = 11.12*sin51 = 8.64 m/s.
January 22, 2015

physics
Increase = (26-(-16))C*1.7*10^-5/C*30cm = 42*1.7*10^-5 * 30cm =0.02142 cm.
January 22, 2015

math
1. (7a^5-a^3) - (a^5-5a^3-1) Remove the parenthesis: 7a^5-a^3 - a^5+5a^3+1 Combine like-terms: 6a^5 + 4a^3 + 1
January 22, 2015

Math
(3x+4)*Log2 4 = (3x+4)*2 = 6x + 8.
January 22, 2015

math
h(t) = -4t^2 + 30t + 1.4 Tr = -B/2A = -30/-8 = 3.75 s. = Rise time. Tf = Tr = 3.75 s. = Fall time. Tr+Tf = 3.75 + 3.75 = 7.5 s. To get under the ball.
January 22, 2015

Math
X Girls. (x+45) Boys. 2x/3 girls passed the test. (4/5)(x+5) = (4x/5 + 4) boys passed test 49 Children failed the test. (x - 2x/3) = x/3 = Girls that failed the test. (X+45) - (4x/5+4) = x/5+41 Boys that failed the test. X/3 + (x/5+41) = 49 x/3 + x/5 = 49-41 = 8 Multiply both ...
January 22, 2015

physics
Incomplete.
January 22, 2015

phyisics
h = 1*sin30 = = 0.5 m. V1^2 = Vo^2 + 2g*h = 0 + 19.6*0.5 = 9.8 V1 = 3.13 m/s. M1*g = 25N. M1*9.8 = 25 M1 = 2.55 kg M2*9.8 = 40N. M2 = 4.08 kg M1*V1 + M2*V2 = M1*V + M2*V 2.55*3.13 + 4.08*0 = 2.55*V + 4.08*V 7.982 = 6.63V V = 1.20 m/s.
January 22, 2015

Math
1b.
January 21, 2015

Physics
X = 64.9 Y = ? Z = 87.6 = magnitude or hypotenuse. X^2 + Y^2 = Z^2 Solve for Y.
January 21, 2015

Physics
2.75*10^19electrons/30s = 9.167*10^17 electrons/s I = (9.167*10^17/62.42*10^17) * 1Amp = 0.147 Amps.
January 21, 2015

physics
Vo = 15.4m/s[34.7o] Xo = 15.4*Cos34.7 = 12.7 m/s. Yo = 15.4*sin34.7 = 8.77 m/s. Y = Yo + g*Tr = 0 @ max.ht. 8.77 - 9.8*Tr = 0 -9.8Tr = -8.77 Tr = 0.895 s. = Rise time. Tf = Tr = 0.895 s. = Fall time. Tr+Tf = 0.895 + 0.895 = 1.79 s. to hit gnd.
January 21, 2015

physics
h = Vo*t + 0.5g*t^2 Vo = 0 t = 2.88 s. g = 9.8 m/s^2 Solve for h.
January 21, 2015

physics
M2V2 = M1V1 0.00255*V2 = 10.7*4.26 Solve for V2.
January 21, 2015

Math proportions
(20min/150people) * 240people = 32 Min.
January 21, 2015

Algebra 2
g(x) = x^2 - 7x - 9 g(-1) = (-1)^2 - 7*(-1) - 9 = -1 F(g(-1)) = F(-1) F(x) = x - 2 F(-1) = -1 - 2 = -3.
January 21, 2015

algebra
m2 = m1 = -A/B = -1/1 = -1 P(0,0), m2 = -1 Y = mx + b = 0 -1*0 + b = 0 b = 0 Y = -1x + 0 Eq2: Y = -x
January 21, 2015

7th grade math
Both answers are correct!
January 21, 2015

Algebra
2(x+3) = 2x+3 2x+6 = 2x+3 2x-2x = 3-6 0 = -3? No
January 21, 2015

algebra
10in./30in. =
January 21, 2015

Math (Greatest common factor)
12 = (1*12), (2*6), (3*4). 18 = (1*18), (2*9), (3*6). 24 = (1*24), (2*12), (3*8), (4*6). CF = 1,2,3,6. GCF = 6. So we factor out 6 and the variables with the lowest exponents: 6m^2n^3(2m^3 + 3m - 4) I, normally, find the GCF by knowing that the GCF =< 12 (the smallest ...
January 21, 2015

Math
1. 6.4in * 2.54cm/in = 2. 4qts * 32oz./qt * 0.03L/oz. = 3. 10kg * 1Lb/0.454kg =
January 21, 2015

Science
B.
January 21, 2015

Science
B.
January 21, 2015

physics
A train whistle is heard at 280Hz as the train approaches town. The train cuts its speed in half as it nears the station, and the sound of the whistle is then 270 Hz. What is the speed of the train before slowing down? What is the speed of the train after slowing down?
January 21, 2015

physics
M1*V1 + M2*V2 = M1*V3 + M2*V3 V3 = V4. 60*0 + 15*12 = 60*V3 + 15*V3 180 = 75V3 V3 = 2.4 m/s = Velocity after impact.
January 21, 2015

physics
a. Y = Yo + g*t = 0 + 9.8*1 = 9.8 m/s = Ver Component. X-component = 0 b. D = 0.5*g*t^2. Solve for D. Y = D, X = 0.
January 21, 2015

physic
a. V = a*t = 0.5m/s^2 * 4s. = 2 m/s. b. d = 0.5a*t^2 = 0.5*0.5*4^2 = 4 m.
January 21, 2015

Physics
T = 12s./10rev = 1.2 s/rev.=1.2 s/cycle
January 20, 2015

Math
sqrt(450) = sqrt(2*225) = 15*sqrt(2).
January 20, 2015

ascience
X = 20 mi/h Y = 10 mi/h Tan A = Y/X = 10/20 = 0.50 A = 26.56o V = X/Cos A = 20/Cos26.56 = 22.4mi/h[26.56o]
January 20, 2015

Physics
Do you mean (5,7)? If so, (x,y) = 5,7).
January 20, 2015

physics
V = Vo + g*t V = 0 Vo = Initial velocity. g = -9.8 m/s^2 t = 2.2 s. Solve for Vo.
January 20, 2015

Math
Yes.
January 20, 2015

math
Bearing of Q = 90-50 = 40o East of North
January 20, 2015

Math
8/25 + 1/5 + x = 4/5 X = 4/5 - 8/25 - 1/5=20/25 - 8/25 - 5/25 = 20/25 - 13/25 = 7/25 of the grid for Nate.
January 19, 2015

physics
Dx = 1710*Cos5.08 =
January 19, 2015

physics
196m[-18o] X = 196*Cos(-18) = Y = 196*sin(-18) =
January 19, 2015

grade 7 math
1. -450 km/h(South). 2. 675 km/h(North). 675T - (-450T) = 3600 km. Solve for T.
January 19, 2015

grade 7 math
A = -80 km/h(West). B = 110 km/h(East). 110T - (-80T) = 760 km 110T + 80T = 760 190T = 760 T = 4 h.
January 19, 2015

grade 7 math
d1 + d2 = 210 km 60*2 + r2*2 = 210 Solve for r2.
January 19, 2015

grade 7 math
9:15 - 8:00 = 1h and 15 min. = 1.25h head-start. d = r1*t = 45km/h * 1.25h = 56.25 km Head-start. r2*t = r1*t + 56.25 t = 9:15AM to 1PM = 3h and 45min = 3.75h r2 * 3.75 = 45*3.75 + 56.25 r2*3.75 = 225 r2 = 60km/h = Michael's speed. r1*t + 56.25 = 45*3.75 + 56.25 = 225 km...
January 19, 2015

grade 7 math
d1 = r1*t1 = 60km/h * 0.5h = 30 km after 0.5 h. r2*t = r1*t + 30 65 * t = 60*t + 30 65t - 60t = 30 5t = 30 t = 6 hours.
January 19, 2015

Physics/Math
a. Eo/Ei = 1.0 100/Ei = 1 Solve for Ei. b. Eo/Ei = 0.30 Eo/100 = 0.30 Solve for Eo. c. Same procedure as a and b.
January 19, 2015

physics
A = 13.2[0o] B = 6.1[110o] R = 13.2+6.1*Cos110 + i6.1*sin110 = 11.11 + 5.73i R^2 = 11.11^2 + 5.73^2 = 156.3 R = 12.50
January 19, 2015

physics
1. D = Vo*t + 0.5a*t^2 = 6.1*6.8 * 0.5*0.49[35o]*6.8^2 = 41.48 + 11.33[35o] = 41.48 + 9.28+6.5.0i = 50.76 + 6.5i D^2 = 50.76^2 + 6.5^2 = 2618.3 D = 51 m. 2. Tan A = Y/X = 6.5/50.76 = 0.12805 A = 7.3o = Direction.
January 18, 2015

physics
M*g = 10kg * 9.8N/kg = 98 N. = Wt. of block. Fn = M*g - Fap*sinA = 98 - 75*sin37 = 52.9 N. Fk = u*Fn = 0.4 * 52.9 = 21.15 N. = Force of kinetic friction. a = (Fap*Cos37-Fk)/M = (75*Cos37-21.15)/10 =
January 18, 2015

Math
Rono: Cost = 4000 + 6*3000 = $22,000 Sam: Cost = 22000 - 5000 =
January 17, 2015

Math
Dan: Cost = 0.90 * 6245 = $5620.50 Dave: Cost = 3000 + 12*500 = $9,000 9000 - 5620.50 =
January 17, 2015

Math
Hali: Cost = 0.95 * 15000 = $14,250 John: Cost = 6000 + 3*3200 = $15,600 15,600 - 14,250 = $1,350 More than Hali.
January 17, 2015

Physics
V = 3km/h[90o] + 40km/h[20o] Y = 3 + 40*sin20 = 16.7km/h = Vertical or Northerly component. d = r*t = 16.7km/h * 6h = 100.1 km.
January 17, 2015

physics
See previous post: Sat,1-17-15, 6:18 PM.
January 17, 2015

physics
Power=Fx * d/t = 70.9*Cos48 * 19.9/4.3 = Note: J/s = Watts.
January 17, 2015

physical science
When they are acting in the same direction. Fmax = 5 + 7 = 12 N.
January 17, 2015

Physics Class
0.450 ms = 0.000450 s. V = Vo + a*t = -36.7 36.7 + a*0.000450 = -36.7 0.00045a = -36.7-36.7 = -73.4 a = -163,111 m/s^2 F = M*a = 0.140 * (-163111) = 22,836 N.
January 16, 2015

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