Thursday

February 26, 2015

February 26, 2015

Total # Posts: 10,138

**Physical science**

AC = AB + BC = 50 + 120 = 170 m. t = d/V = 170/5 = 34 s.
*November 15, 2014*

**Physical science**

AC = AB + BC = 50 + 120 = 170 m.
*November 15, 2014*

**math**

See previous post: Sat, 11-15-14, 4:37 AM.
*November 15, 2014*

**math**

sqrt(N) = (N)^1/2. D^2 = (4*2^1/2-3^1/2)^2 + (6^1/2+2)^2 = 35.2 D = 5.933 cm.
*November 15, 2014*

**MATH**

The sqrt(N) = (N)^1/2. (m+3)^1/2 + (m-2)^1/2 = 5 m+3)^1/2 = 5 - (m-2)^1/2 Square both sides: m+3 = 25 - 2*5*(m-2)^1/2 + m-2 m+3 -m+2 = 25 - 10(m-2)^1/2 5 = 25 - 10(m-2)^1/2 Divide both sides by 5: 1 = 5 - 2(m-2)^1/2 2(m-2)^1/2 = 5-1 = 4 Square both sides: 4(m-2) = 16 4m - 8 = ...
*November 15, 2014*

**math**

TanA = Y/X = 5/6
*November 15, 2014*

**physical**

P2(-3,-4), P1(3,4). P1 - P2: X = 3-(-3) = 6 Meters. Y = 4-(-4) = 8 Meters. (X,Y) = (6,8).
*November 14, 2014*

**physics**

M =0.009 kg PE = Mg*h = 0.009*9.8*4.0 = 0.3528 J.
*November 14, 2014*

**math**

A = 11/16 * 256 = 176
*November 14, 2014*

**Physics**

m*g = 130kg * 9.8N./kg = 1274 N. Fn = m*g = 1274 N. Fk = u*Fn = 0.35 * 1274 = 446 N. = Force of kinetic friction. a = (Fap-Fk)/m = (-800-446)/130 = -9.58 m/s^2 V2^2 = V1^2 + 2a*d = 0 d = -V1^2/2a = -(10.2^2)/-19.17 = 5.43 m. = Stopping distance. Note: The force applied is ...
*November 13, 2014*

**6th grade math**

Baby eats X Lbs. Male eats 3x Lbs. Female eats 2x Lbs. x + 2x + 3x = 181.5 Lbs. Solve for x.
*November 13, 2014*

**Math**

2 * 48 = 96 Ounces 96/8 = 12- Eight oz. classes.
*November 13, 2014*

**physics**

F = m*a
*November 13, 2014*

**Physics-Atwood's Machine**

m*g = 5kg * 9.8N./kg = 49 N. Fk = u*mg = 0.5 * 49 = 24.5 N. = Force of kinetic friction. Fx-Fk = m*a Fx-24.5 = 5 * 3 = 15 Fx = 15 + 24.5 = 39.5 N.
*November 13, 2014*

**science**

m*g = 40 N. 4.20g = 40 g = 9.52 m/s^2 a = F/m = 45.5/4.20 = 10.83 m/s^2.
*November 13, 2014*

**Math help please!!!!!!**

C is correct.
*November 13, 2014*

**physics**

Yo = 141*sin45 = 99.7 m/s.
*November 13, 2014*

**physics**

Momentum = m*V = 0.1 * 500
*November 13, 2014*

**physics**

M = 4.5 kg h = 1500cm = 15 m. F = 1861N/m * 0.12m = 223.32 N. a = F/m = 223.32/4.5 = 49.63 m/s^2 V2^2 = V1^2 + 2a*h=0 + 99.25*15=1488.8 V2 = 38.6 m/s = Speed of block.
*November 12, 2014*

**Freshman Algebra**

Private plane: 500km/h * 1h = 500km Head-start. d1 + d2 = 2100 km 500+500t + 700t = 2100 1200t = 2100-500 = 1600 t = 4/3 = 1 1/3 Hours(1:20 PM).
*November 12, 2014*

**Physics (Work Problem)**

a. Work = Fx * d = 50*Cos30 * 10 = 433 J
*November 12, 2014*

**physics**

Correct!
*November 12, 2014*

**Physics**

g/2^2 = g/4.
*November 12, 2014*

**Physics**

F = 110N[45o] Fx = 110*Cos45 = 77.78 N.
*November 12, 2014*

**Science**

T = 1/F = 1/0.5 = 2 s. = Period = Time between crests. WL = V*T = 6 m. V * 2 = 6 V = 3 m/s.
*November 12, 2014*

**Physics**

a. d1 = 0.5a*t^2 = 0.5*1.3*5.9^2=22.63 m V1 = a*t = 1.3 * 5.9 = 7.67 m/s. V = V1 + a*t = 7.67 - 1.7*1.6 = 4.95 m/s b. d1 = 0.5a*t^2 = 0.5*1.3*5.9^2=22.63 m d2 = (V^2-V1^2/2a = (4.95^2-(7.67^2))/-3.4 = 10.1 m. d = d1+d2 = 22.63 + 10.1 = 32.73 m
*November 12, 2014*

**physics**

d = 4.3*10^-6cm/s * 3600s/h * 8760h/yr. * 6.4yrs. = 868 cm.
*November 11, 2014*

**math**

Your problem would be easier to under- stand if you proof-read it and show punctuations.
*November 11, 2014*

**Math**

Log2(x+4) = Log2(x^2+2) x + 4 = x^2 + 2 x - x^2 = 2 - 4 -x^2 + x = -2 -x^2 + x + 2 = 0 Multiply both sides by -1: x^2 - x - 2 = 0 -2 = -2*1. Sum = -2 + 1 = -1 = B. x+(-2)) = 0 x-2 = 0 X = 2 x+1 = 0 X = -1 Solution: X = -1, and 2.
*November 11, 2014*

**physics**

Work = Fx*d = 148*Cos35 * 2 = 242.5 N.
*November 11, 2014*

**physics**

Wt. = (1.61/9.8) * 54.3N. = 8.92 N.
*November 11, 2014*

**physics**

KE = m*V^2/2 2KE = m*V^2 m = 2KE/V^2 m*V^2 = 2KE V^2 = 2KE/m V = Sqrt(2KE/m)
*November 11, 2014*

**physics**

d = 0.5a*t^2 = 122.1 m. 2.4*t^2 = 122.1 t^2 = 50.875 t = 7.13 s. V = a*t = 4.8 * 7.13 = 34.2 m/s.
*November 10, 2014*

**physics**

h = 0.5*t^2 = 125 m. 4.9t^2 = 125 t^2 = 25.51 Tf = 5.05 s. = Fall time. Dx = Xo * Tf = 144m/s * 5.05s = 727 m. From the cliff.
*November 10, 2014*

**Math**

10yds * 36in/yd. = 360 In. 360in * 1ribbon/6in. = 60 Ribbons.
*November 10, 2014*

**Math**

It could mean 12 squared = 12*12 = 12 raised to the 2nd power = 144.
*November 10, 2014*

**math**

1/5x^(-1/2) = x^(1/2)/5.
*November 10, 2014*

**maths**

See previous post: Sun, 11-9-14, 11:00 AM.
*November 10, 2014*

**math**

Length = L Width = L/3 P = 2L + 2L/3 = 40 cm. Solve for L.
*November 10, 2014*

**physics**

Vo = 58.2km/h = 58200m/3600s. = 16.2 m/s a = u*g = 0.155 * -9.8 = -1.52 m/s^2. V^2 = Vo^2 + 2a*d = 0 d = -(Vo^2)/-2a = -(16.2^2)/-3.04 = 86.3 m.
*November 10, 2014*

**physics**

Tf = Tr = 5.8/2 = 2.9 s. Tr = Rise time. Tf = Fall time. h = 0.5g*Tf^2
*November 9, 2014*

**Math**

Incomplete.
*November 9, 2014*

**Check my physics answer**

When the arrow points toward the negative x axis.
*November 9, 2014*

**physics**

m*g = 75.95 N. = Wt. of the box. Fp = 75.95*sin29.7 = 37.63 N. = Force parallel to the ramp. a = (Fp-Fk)/m a = (37.63-5.88)/7.75 = 4.1 m/s^2 V^2 = Vo^2 + 2a*d = 0 + 8.2*3.11 = 25.5 V= 5.05 m/s = Xo = Initial hor. velocity. h = 0.5g*t^2 = 0.84 m. 4.9*t^2 = 0.84 t^2 = 0.171 Tf...
*November 9, 2014*

**Physics**

Vo = 22 m/s. u = 0.68 a = u*g = 0.68 * -9.8 = -6.66 m/s^2. V = Vo + a*t = 0 t = -Vo/a = -22/-6.66 = 3.30 s.
*November 9, 2014*

**physics**

m*g = 65 * 9.8 = 637 N. = Force of skier. Fp = 637*sin15 = 164.9 N. = Force parallel to the incline. Fn = 637*cos15 = 615.3 N. = Normal force = Force perpendicular to the incline. Fk = u*Fn = 0.25 * 615.3 = 153.8 N. = Force of kinetic friction. a = (Fap-Fp-Fk)/m. Fap = 500 N...
*November 9, 2014*

**physics 1**

Incomplete.
*November 9, 2014*

**Algebra 2**

+3x + 3y - z = -3 -2x - 3y + 2z = 3 x - 6y + 3z = 0 Eq1: 3x + 3y - z = -3 Eq2: -2x - 3y + 2z = 3 Sum: x + 0 + z = 0 z = -x Eq2: -2x - 3y + 2z = 3 Eq3: x - 6y + 3z = 0 Multiply Eq2 by 6 and Eq3 by (-3): -12x - 18y + 12z = 18 -3x + 18y - 9z = 0 Sum: -15x + 0 + 3z = 18 Replace z ...
*November 9, 2014*

**physical science**

a = (Fap-Ff)/M = (40-24)/8 = 2 m/s^2.
*November 9, 2014*

**maths**

(3/8+2/8) * 128 = (5/8) * 128 = 80 cards given away.
*November 9, 2014*

**Physics**

M*g = 178 N. Vo = 0.5 m/s. Ramp = 3m[24o] Fp = 178*sin24 = 72.4 N. = Force parallel to the ramp. M*g = 178 M = 178/g = 178/9.8 = 18.16 kg = mass of box. a = Fp/M = 72.4/18.16 = 3.99 m/s^2.
*November 9, 2014*

**Math**

Incomplete.
*November 9, 2014*

**Physics test review**

h = 30.1 m. Dx = 66.8 m. 1. h = Yo*t + 0.5g*t^2 = 30.1 0 + 4.9t^2 = 30.1 t^2 = 6.143 Tf = 2.48 s. = Fall time or time in motion. 2. Dx = Xo*Tf = 66.8 Xo * 2.48 = 66.8 Xo = 27 m/s. = Initial velocity. 3. X = Xo = 27 m/s = X component of velocity just before it hits gnd. 4. Y^2...
*November 8, 2014*

**word problem math b**

Posts = 4 + (2*L/10) + (2*W/10)
*November 7, 2014*

**Math**

16pi/5 = 16*180/5 = 576o = 1.6 Rev. A = 0.6Rev * 360o/Rev = 216o, Q3. In Q3, A - Ar = 180o 216 - Ar = 180 Ar = 36o = Reference angle. Ar = (36o/360o) * 2pi = 2pi/10 Radians. Notes: In Q2, A + Ar = 180o In Q4, A + Ar = 360o
*November 7, 2014*

**math**

Tot. Funds=16*$1.00 + 5*5.00 + 5*10.00 + 3*20.00 + 4*0.05 + 20*0.10 + 16*0.25 + 66.00 + 53.75 Deposit = Tot. funds - 50.00
*November 7, 2014*

**physics**

Incomplete.
*November 7, 2014*

**physics**

False. The force of kinetic friction is smaller.
*November 7, 2014*

**CAL- derivative **

Find the derivative; y= x^3(5x-1)^4 So this is my answer y'=2x(5x-1)^3 + 10x + x(5x-1) Please correct me if my answer is wrong.
*November 7, 2014*

**Algebra**

10*Log(2.50*10^5/10^-16) = 10*Log(2.50*10^21) = 214 db.
*November 7, 2014*

**physics**

Vo = 1630 m/s[86o] Yo = 1630*sin86 = 1626 m/s. Y = Yo + g*Tr = = 0 @ max Ht. Tr = -Yo/g = -1626/-9.8 = 166 s. = 2.77 Min. Tf = Tr = 2.77 min. = Fall time. Tr + Tf = 2.77 + 2.77 = 5.54 Min. = Time in flight.
*November 6, 2014*

**physics**

d = 7.6 m. h = 0.5g*t^2 = 3.3 m. Solve for t. Xo = d/t m/s = Initial Hor. velocity
*November 6, 2014*

**science**

a = F/m = 85/5 = 17 m/s^2. V = Vo + a*t = 14 + 17*20 = 354 m/s.
*November 6, 2014*

**math**

Tan20 = h/d = 50/d d = 50/Tan20 = 137.4 m.
*November 6, 2014*

**science.**

The law of conservation of momentum says it will be the same.
*November 6, 2014*

**physics**

V^2 = Vo^2 + 2g*h Vo = 0 2g = 19.6 m/s^2 h = 35 m. Solve for V.
*November 6, 2014*

**Math, Please Help!**

X student tickets sold. (723-X) Non-student tickets sold. 3x + 5(723-X) = $2,815. Solve for X.
*November 6, 2014*

**Physics**

A. m*g = 19kg * 9.8N/kg = 186.2 N. = Force of the suitcase. u = a/g, a = u*g = 0.54 * 9.8 = 5.29 m/s^2 Fn = mg-F*sin41.3 = 186.2-0.66F = Normal force. F*Cos41.3-.54(186.2-0.66F) = 19*5.29 0.751F - 100.5 + 0.356F = 100.5 1.107F = 201 F = 181.6 N. = Force applied. Fn = 186.2 - 0...
*November 6, 2014*

**nqwiliso s.s.s.**

Fr = 30 + 25 + (-40) = 15 N.,Headed East
*November 6, 2014*

**Pre Algebra**

Sqrt(25) + (-9) = -4 = A Whole number.
*November 6, 2014*

**physics**

(1rev/0.4s) * 60s./min = 150 RPM.
*November 6, 2014*

**physics**

F = m*g = 1*9.8 = 9.8 N k = F/d = 9.8N/0.012m = 816.7 N/m.
*November 6, 2014*

**Math**

1. Log(9/300) = Log 9 - Log 300 2. Log2(4^2*3^4) = Log2(4^2) + Log2(3^4) = Log2(16) + Log2(81)
*November 6, 2014*

**Science**

F1+F2 = m*a = 0.750 * 0.450 = 0.3375 N. Fi-F2 = 0.750 * 0.240 = 0.18 N. Eq1: F1 + F2 = 0.3375 Eq2: F1 - F2 = 0.1800 Sum: 2F1 = 0.5175 F1 = 0.25875 N. In Eq1, replace F1 with 0.25875 0.25875 + F2 = 0.3375 F2 = 0.3375 - -0.25875 = 0.07875 N.
*November 6, 2014*

**physics**

See previous post: Thu, 11-7-14, 6:30 AM.
*November 6, 2014*

**physics**

See previous post: Thu, 11-7-14, 6:30 AM.
*November 6, 2014*

**physics**

d = V*T = 3.50 km T = 3.50/V = 3.50/25 = 0.14 h. T = 3.50/40 = 0.0875 h. 0.14 - 0.0875 = 0.0525 h = 3.15 Min. gained.
*November 6, 2014*

**phisics**

Fap = mg*sin45 = 36 N. m = 36/g*sin45 = 5.2 kg Fap = Force applied.
*November 6, 2014*

**algebra**

3.65V^2 + 0.0875V^2/0.09 = 62.7 3.65V^2 + 0.9722V^2 = 62.7 4.622V^2 = 62.7 V^2 = 13.56 V = 3.68
*November 5, 2014*

**physics**

Fd = (Vs+Vd)/(Vs-Va)*Fa = 1050 Hz. (340+0)/(340-Va) * 980 = 1050 Divide both sides by 980: 340/(340-Va) = 1.0714 364.29-1.0714Va = 340 -1.0714Va = 340-364.29 = -24.29 Va = 22.7 m/s. = Velocity of the ambulance. Vs = Velocity of sound. Vd = Velocity of the detector.
*November 5, 2014*

**algebra**

V^2 = Vo^2 + 2g*h = 0 + 64*203 = 12,992 V = 114 Ft/s.
*November 5, 2014*

**Algebra**

V = 8*sqrt(h) = 8*sqrt(203) = 114 Ft/s.
*November 5, 2014*

**physics**

V^2 = Vo^2 + 2g*h = 0 + 19.6*(10-5) = 98 V = 9.90 m/s @ 5 m above the surface. V^2 = 0 + 19.6*10) = 196 V = 14 m. Just before striking the surface.
*November 5, 2014*

**science**

Incomplete.
*November 5, 2014*

**physics**

Vo = 10 m/s. V = 5 m/s. d = 150 m. a = ? a. V^2 = Vo^2 + 2a*d a = (V^2-Vo^2)/2d = b. d = (V^2-Vo^2)/2a. V = 0, Vo = 5 m/s.
*November 5, 2014*

**Physics**

Incomplete.
*November 4, 2014*

**Algebra**

F(x) = Y = -x^2 + 6x + 6 = 0 Use Quadratic Formula. (X, Y) = (-2, 0), (8, 0).
*November 4, 2014*

**Precalculus**

Do you mean e^2x - 1 = e^4 or e^(2x-1) = e^4. I will assume the 2nd Eq. (2x-1)*Ln e = 4*Ln e (2x-1)*1 = 4*1 2x-1 = 4 2x = 5 X = 5/2 = 2.5
*November 4, 2014*

**physics**

a. a = (V-Vo)/t. V = 510 m/s Vo = 0 t = 2.37 s. b. a = (V-Vo)/t V = 0 Vo = 510 m/s. t = 3.15 s. Note: Acceleration when braking will be negative.
*November 4, 2014*

**physics**

V^2 = Vo^2 + 2g*h. Vo = 0 @ top of hill. V^2 = 2g*h. Solve for V.
*November 4, 2014*

**physics**

V^2 = Vo^2 + 2g*h = 0 + 19.6*2000 = 3920 V = 62.6 m/s. KE = 0.5m*V^2 = 50*62.6^2 = 195,938 J.
*November 4, 2014*

**physics**

m*g = 180kg * 9.8N/kg = 1764 N. PE = mg*h = 8000 J @ top of hill. h = 8000/mg = 8000/1764 = 4.54 m.
*November 4, 2014*

**Math**

(40/360) * 2p1 = 2pi/9 Radians.
*November 4, 2014*

**Science**

a = (Fap-Ff)/m = (25-6)/1.5 =
*November 4, 2014*

**Physics**

A vector quantity shows magnitude and direction: 50 m/s @ 45o. Magnitude = 50 m/s. Direction = 45 Degrees.
*November 4, 2014*

**physics**

F1+F2+F3 = 72.7N[0o] + 79.9N[45o] + 103N[315o]. X = 72.7 + 79.9*Cos45 + 103*Cos315=202 N Y = 79.9*sin45 + 103*sin315 = -16.33 N. F^2 = X^2 + Y^2 = 202^2 + (-16.33) = 41,071 F = 203 N. = Resultant force. Tan A = Y/X = -16.33/202 = -0.08084 A = -4.62o = 4.62o S. of E. = Direction.
*November 3, 2014*

**science**

1. The DF increases: DF = PW/PRF. 2. The PRF increases: PRF = 1/PRP. 4. When WL decreases, the PRF increases. The increase in PRF decreases the DF. PRF = V/WL
*November 3, 2014*

**physics**

A = (27.1-9.1)*7.7*10^-4 * 5 = 0.0693 Gal.
*November 3, 2014*

**science**

incomplete.
*November 3, 2014*

**Physics**

D = 4.19*Cos10.4
*November 3, 2014*

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