Friday

August 22, 2014

August 22, 2014

Total # Posts: 8,929

**Physics**

a. V = d/t = 2.0m/1.75s. = 1.143 m/s. V^2 = Vo^2 + 2a*d a = (V^2-Vo^2)/2d a = (1.143^2-o)/4 = 0.327 m/s^2 b. Wb = m*g = 3kg * 9.8N/kg = 29.4 N. = Weight of block. Fp = 29.4*sin25.5 = 12.66 N. = Force parallel to incline. Fv = 29.4*cos25.5 = 26.54 N. = Force perpendicular to ...
*October 23, 2013*

**physics**

Wc = m*g = 19kg * 9.8N/kg = 186.2 N. = Weight of crate. Fap-Fs = m*a 83-u*mg = m*0 83-u*186.2 = 0 186.2u = 83 us = 0.446 uk*186.2 = 53 uk = 0.285
*October 23, 2013*

**physic**

g = 9.8 m/s^2
*October 22, 2013*

**Finance**

a. 1/A = 0.08 0.08A = 1 A = $12.5 Million. b.
*October 22, 2013*

**science**

1. mass/cm^3 = Density = 20g/10cm^3 = 2g/cm^3 = 0.002kg/cm^3. 2. Density = 125g/25cm^3 = 5 g/cm^3 = 0.005kg/cm^3.
*October 22, 2013*

**math**

r1 = 40km/0.5h = 80 km/h = Stephen's speed. r2=Cole's speed = 80 + 30 = 110 km/h. r2 * t = (r1 * t) + 40km 110t = 80t + 40 30t = 40 t = 1.33 h. D = r*t = 110 * 1.333 = 146.7 km. = Distance between the 2 towns.
*October 22, 2013*

**physics**

d = 100 - 50 = 50 Meters.
*October 22, 2013*

**MATH**

Marit ate 12 crackers/day. Jennifer ate 12+6 = 18 crackers/day. Difference = 96-24 = 72 crackers 72Crackers/6Crackers/day = 12 Days Marit=12crackers/day * 12Days=144 Crackers. Jennifer=18crackers/day*12days=216 crackers.
*October 22, 2013*

**Math**

X = # of oranges. X = # of pears. ($2/7) * X = $Y Multiply both sides by 7: 2x = 7y Eq1: 2x - 7y = 0 ($3/5) * X = y + 33 Multiply both sides by 5: 3x = 5y + 165 Eq2: 3x - 5y = 165 Multiply Eq1 by 3 and Eq2 by -2 and add: +6x - 21y = 0 -6x + 10y = -330 Sum: -11y = -330 Y = $30...
*October 22, 2013*

**GEOMETRY**

5*Sqrt(3/3)=5*Sqrt(1)=5*1 = 5.
*October 21, 2013*

**Physics**

Tf = Tr = 2.80 s. = Fall time.
*October 21, 2013*

**Physics**

Vp + Vw = 410mi/h[310o]+50mi/h[295o]. X = 410*cos310 + 50*cos295 = 284.7 mi/h Y = 410*sin310 + 50*sin295 = -359.4 mi/h tanA = Y/X = -359.4/284.7 = -1.26236 A = -51.6 = 51.6o S. of E. Vr = Y/sin(-51.6) = 459 mi/h
*October 21, 2013*

**physics**

Incomplete.
*October 21, 2013*

**physics**

1. V = a * t = 20 m/s. a * 10 = 20 a = 2 m/s^2. 2. V = Vo + a*t = 0 20 + a*20 = 0 20a = -20 a = -1.0 m/s^2.
*October 21, 2013*

**Physics**

Fg = m*g = 10kg * 9.8N/kg = 98 N. d = (98/400) * 1m = 0.245 m.
*October 21, 2013*

**physics**

1. V^2 = Vo^2 + 2g*h V^2 = 0 + 19.6*3 = 58.8 V = 7.67 m/s. 2.
*October 21, 2013*

**Physics**

(1/12) * 60s = 5 s. per brick. P = F * d/t = mg * d/t P = 3.75*9.8 * 3.3/5=24.26 J/s=24.26 W. (24.26/746) * 1hp = 0.0325 hp.
*October 21, 2013*

**phyics**

V^2 = Vo^2 + 2g*h (Vo/2)^2 = Vo^2 + 2g*h Vo^2/4 = Vo^2 - 19.6*5 Vo^2/4 = Vo^2 - 98 Multiply both sides by 4: Vo^2 = 4Vo^2 - 392 4Vo^2 - Vo^2 = 392 3Vo^2 = 392 Vo^2 = 130.7 Vo = 11.43 m/s. hmax = (V^2-Vo^2)/2g h max = (0-11.43^2)/-19.6 = 6.67 m.
*October 20, 2013*

**Physics**

Incomplete.
*October 20, 2013*

**physics**

CORRECTION: Y^2 = 0 + 19.6*(4.82-3) = 35.67 Y = 5.97 m/s.
*October 20, 2013*

**physics**

Vo = 14.2m/s[43.2o] Yo = 14.2*sin43.2 = 9.72 m/s. hmax = (Y^2-Yo^2)/2g hmax = (0-9.72^2)/19.6 = 4.82 m. Y^2 = Yo^2 + 19.6*h Y^2 = 9.72^2 + 19.6*(4.82-3) = 130.15 Y = 11.41 m/s
*October 20, 2013*

**Physics**

Incomplete.
*October 20, 2013*

**physics**

Fn = mg*cos16 = 5.7*9.8*cos16 = 53.7 N.
*October 20, 2013*

**physics**

Dx = Vx * Tf = 20 m. 27.1 * Tf = 20 Tf = 0.738 s. = Fall time. h = Yo*Tf + 0.5g*Tf^2 h = 0 + 4.9*0.738^2 = 2.67 m.
*October 20, 2013*

**physics**

Va = 72rev/2s * 1cy/rev = 36/cycles/s.
*October 20, 2013*

**Physics**

Fg = m*g = 0.245kg * 9.8N/kg = 2.401 N.= Force of gravity. D = d1 + d2 d1=(V^2-Vo^2)/2g=(0-8.8^2)/-19.6=3.951 m Up. d2 = d1 + 2.20 = 3.951 + 2.20 = 6.15 m, Down. Wg = Fg*(d1+d2)=2.401*(3.951+6.15)=24.3 Joules.
*October 20, 2013*

**Physics**

See previous post: Sun,10-20-13,2:57 PM.
*October 20, 2013*

**Physics**

Fx = 35.9*cos28.7 = 31.49 N. = Hor. component. Work=Fx*d = 31.49 * 3.41 = 107.4 Joules
*October 20, 2013*

**Physics**

X = 3 m/s. Y = -2 m/s. a. (Vr)^2 = X^2 + Y^2 = 3^2 + (-2)^2=13 Vr = 3.61 m/s. = Resultant velocity. b. tan A = Y/X = -2/3 = -0.66666 A = -33.7o = 33.7o S. of E. Therefore, she must swim 33.7o N. of E.
*October 20, 2013*

**Projectile motion**

h = (Vo*sin(-30))*(t) + 0.5g*t^2=15 m. (Vo*sin(-30))*(3) + 4.9*3^2 = 15 -1.5Vo + 44.1 = 15 -1.5Vo = 15-44.1 = -29.1 Vo = 19.4 m/s.
*October 20, 2013*

**math**

Incomplete.
*October 20, 2013*

**Science/Physics**

Very fast!
*October 20, 2013*

**PHYSICS**

V^2 = Vo^2 + 2g*h h = (V^2-Vo^2)/2g h = (0-5^2)/-20 = 1.25 m. V = Vo + g*t t = (V-Vo)/g = (0-5)/-10 = 0.5 s.
*October 19, 2013*

**physics**

See previous post.
*October 19, 2013*

**physics**

Correction: Fv = 49,000*cos15 = 47,330 N,
*October 19, 2013*

**physics**

W = m*g = 5000kg * 9.8N/kg = 49,000 N.= Weight of truck. Fp = 49000*sin15 = 12,682 N. = Force parallel to ramp. Fv = 4900*cos15 = 47,330 N. = Force perpendicular to the ramp. Fk = u*Fv = 0.10 * 47,330 = 4733 N. = Force of kinetic friction. T-Fp-Fk = m*a T-12682-4733 = m*0 = 0 ...
*October 19, 2013*

**Finance**

P = n*Po*(1+r)^t P = 4*6400(1.057)^4 = $31,955.08
*October 19, 2013*

**Physics**

1. d = 0.5g*t^2 = 3 m. 4.9t^2 = 3 t^2 = 0.6122 T = 0.782 s. To cross canyon. 2. 3 m.
*October 17, 2013*

**Physics**

C = (14/500) * 1m = 0.028 m.
*October 17, 2013*

**Math**

1.23*10^-10/1.4*10^-8 = 0.879*10^-2 = 8.79*10^-3. When dividing, subtract the exponents: -10 - (-8) = -10 + 8 = -2.
*October 17, 2013*

**Physics**

See previous post: 10-17-13,5:26 PM.
*October 17, 2013*

**physics**

Wc = m*g = 3100kg * 9.8N/kg = 30,380 N.= Wt. of car. Fp = 30,380*sin19.5 = 10,141 N. = Force parallel to incline. Fv = 30,380*cos19.5 = 28,637 N. = Force perpendicular to incline. Fk=4400 N. = Force of kinetic friction. Fp-Fk = m*a a=(Fp-Fk)/m a = (10,141-4400)/3100=1.852 m/s^...
*October 17, 2013*

**physics**

1. V = 90km/h = 90000m/3600s. = 25 m/s. a = (V-Vo)/t = (25-0)/8 = 3.125 m/s^2. t = 42-18 = 24 s. To catch up. d = Vo*t + 0.5a*t^2 d = 0 + 0.5*3.125*24^2 = 900 m. 2. d = V*t = 900 m. V * 42 = 900 V = 21.43 m/s.
*October 17, 2013*

**physics**

Vo = a * t = 29.4 * 5.65 = 166.1 m/s. V^2 = Vo^2 + 2g*h h=(V^2-Vo^2)/2g=(0-166.1^2)/-19.6=1408 m
*October 17, 2013*

**maths**

See previous post.
*October 17, 2013*

**maths**

The 1st(closest) car: X1 = Distance from tower. A1 = 60o = Angle between X1 and hyp. The 2nd car: X2 = Dist. bet. the 2 cars. X1+X2 = Dist. from 2nd car to tower. A2 = 30o = Angle bet. (X1+X2) and hyp. tan 60 = 50/X1 X1 = 50/tan 60 = 28.87 m. tan 30 = 50/(X1+X2) X1+X2 = 50/tan...
*October 17, 2013*

**Physics**

If there is no angle between the vectors, the sum = 200 + 40 = 240.
*October 17, 2013*

**physics**

Xo = 2 m/s. h = 0.5g*t^2 = 1 m. 4.9t^2 = 1 t^2 = 0.204 Tf = 0.452 s. = Fall time. Dh = Xo * Tf = 2m/s * 0.452 = 0.904 m = Hor. distance from table. d = Dh - r = 0.904 - 0.05 = 0.854 m = Hor. distance from table.
*October 17, 2013*

**Physics**

See previous post: Wed,10-16-13,2:01 PM>
*October 16, 2013*

**Physics**

Dc = Vo*t + 0.5a*t^2 = 27t+60 41t + 0.5*5*t^2 = 27t + 60 41t -27t + 2.5t^2 = 60 14t + 2.5t^2 = 60 2.5t^2 + 14t - 60 = 0 Use Quadratic formula. t = 2.84 s. To catch up. Vc = Vo + a*t = 41 + 5*2.84 = 55.2 m/s.
*October 16, 2013*

**physics**

Incomplete.
*October 16, 2013*

**Physics**

Incomplete.
*October 16, 2013*

**Physics**

1. d = 1.7 + 7.1 + 3.5 = 12.3 km. 2. D = 1.7 -7.1 + 3.5 = -1.9 km = 1.9 km , West.
*October 16, 2013*

**Physics**

Ct = C1*C2/(C1+C2) = 8.3*2.9/(8.3+2.9) = 2.15 uF Qt = Ct*E = 2.15 * 24 = 51.6 uC.=Q1=Q2. Energy=0.5C*E^2 = 0.5*2.15*24^2 =619.2 Joules Parallel Combination: Ct = C1 + C2 = 8.3 + 2.9 = 11.2 uF. Energy = 0.5*Ct*E^2 = 619.2 Joules 0.5*11.2*E^2 = 619.2 5.6E^2 = 619.2 E^2 = 110.6 E...
*October 16, 2013*

**physics**

Please post your problem.
*October 16, 2013*

**Physics**

X = 75 m/s. Y = 100 m/s. Q1. tan A = Y/X = 100/75 = 1.33333 A = 53.1o V=Y/sin A = 100/sin53.1 = 125.0N.[53.1o] Q2. Direction = 90o-53.1o=36.9o W of N.
*October 16, 2013*

**Physics**

Same procedure as previous post
*October 16, 2013*

**Physics**

F = 152N[35o] Fx = 152*cos35 = Fy = 152*sin35 =
*October 16, 2013*

**Physics**

X = 13.5 N. Y = 32 N. tan A = Y/X = 32/13.5 = 2.37037 A = 67.1o Fr = 32/sin 67.1 = 34.7 N[67.1o] = Resultant force. Equilibrant=34.7N[67.1+180]=34.7N[247.1]
*October 16, 2013*

**Math- Urgent**

W/4 = -13 Multiply both sides by 4: W = 4*-13 = -52.
*October 16, 2013*

**Physics**

a. C = C1*C2/(C1+C2) = 30 uF 33.6*C2/(33.6+C2) = 30 33.6C2 = 1008+30C2 33.6C2-30C2 = 1008 3.6C2 = 1008 C2 = 280 uF In series. b. C1 + C2 = 30 uF 29.3 + C2 = 30 C2 = 30 - 29.3 = 0.7 uF in parallel.
*October 15, 2013*

**science**

Incomplete.
*October 15, 2013*

**physics**

Fap-Fk = m*a Eq1: 77 - Fk = m*0.45 Eq2: 82 - Fk = m*0.74 Subtract Eq2 from Eq1: Diff. = -5 = -29m m = 0.172 kg.
*October 15, 2013*

**Physical Science**

W = (1/6)(100kg*9.8N/kg) = 163.3 N.
*October 15, 2013*

**Physical Science**

d.
*October 15, 2013*

**math**

Scale = 1cm:0.6m = 1cm:60cm V = (60/1)*(34 x 20 * 6) V = 2040 x 1200 x 360 cm.
*October 15, 2013*

**Algebra 2**

24. Eq1: 4x + 5y = 3 Eq2: 6x + 9y = 9 Multiply Eq1 by 6 and Eq2 by -4 and add: 24x + 30y = 18 -24x - 36y = -36 Sum: -6y = --18 Y = 3 In Eq1, replace y with 3 and solve for x: 4x + 5*3 = 3 4x = 3-15 = -12 X = -3 26. Use same procedure as #24. Multiply Eq1 by 2 and Eq2 by -4 and...
*October 15, 2013*

**physics**

d = 2.12m/s * 0.21s = 0.4452 m. C=(6.28rad/2.10rad) * 0.4452 m=1.33 m. = Circumference. C =3.14 * 2r = 1.33 m. 6.28r = 1.33 r = 0.212 m. = Radius of the wheel.
*October 15, 2013*

**Physics**

V^2 = Vo^2 + 2a*d a = (V^2-Vo^2)/2d a = (372.4^2-0)/1 = 138,682 m/s^2 F = m * a = 0.0042 * 138,682 = 582.5 N.
*October 15, 2013*

**phydraulic**

Work = 2000 * 2 = 4000 Ft-Lbs.
*October 15, 2013*

**phyiscs**

t=(v-Vo)/a = (25-10)/(0.5*9.8) =3.06 s.
*October 15, 2013*

**physics**

H = 0.5g*t^2 = 32.3 m. 4.9t^2 = 32.3 t^2 = 6.59 t = 2.57 s.
*October 14, 2013*

**physics**

t = 10.2min * 60s/min = 612 s. P = F * d/t = mg * d/t P = 38*9.8 * 170/612 = 103.4 J/s
*October 14, 2013*

**Science**

KE = 0.5m*V^2 = 43.2 J. m = 0.3 kg, solve for V,
*October 14, 2013*

**Science**

PE = mg*h = 2700 J. 45 * 9.8 * h = 2700 Solve for h.
*October 14, 2013*

**physics**

Vo = 16m/s[55o] Yo = 16*sin55 = 13.11 m/s. Y^2 = Yo^2 + 2g*h h = (Y^2-Yo^2)/2g h = (0-13.11^2)/-19.6 = 8.77 m.
*October 14, 2013*

**math**

I = Po*(r/365)*t = $1307 I = 45000*(.04/365)*t = 1307 4.932t = 1307 t = 265 Days.
*October 14, 2013*

**Physics**

See previous post: Mon,10-14-13,2:31 PM.
*October 14, 2013*

**Physics**

Wc = m * g = 149kg * 9.8N/kg = 1460 N. = Wt. of the crate. Fp = 1460*sin51 = 1135 N. = Force parallel to the plane. Fv = 1460*cos51 = 919 N. = Force perpendicular to the plane. Fap-Fp = m*a Fap-1135 = m*0 = 0 Fap = 1135 N. = Force applied parallel to the plane. Fh = Fap*cos51...
*October 14, 2013*

**PHYSICS**

a. Ct = C1*C2?(C1+C2) Ct = 7*11/(7+11) = 4.28 uF. = Total capacitance. b. Qt = Ct*V = 4.28 * 9 = 38.5 uC=Q1=Q2 Q1 = C1*V1 = 38.5 7 * V1 = 38.5 V1 = 5.5 Volts. C2 * V2 = Qt V2 = 38.5/11 = 3.5 Volts. c. Q1 = Q2 = Qt = 38.5 uC.
*October 14, 2013*

**physics**

Range = Vo^2*sin(2A)/g Range = Vo^2*sin(60)/9.8 = 40 0.08837Vo^2 = 40 Vo^2 = 452.6 Vo = 21.3 m/s
*October 14, 2013*

**physic**

Ion.
*October 14, 2013*

**physic**

Ion.
*October 14, 2013*

**phy 111**

See previous post: Mon,10-14-13,8:26 AM.
*October 14, 2013*

**phy 111**

Fr = 100N[170o] + 100[50o] X = 100*cos170 + 100*cos50 = -34.2 N. Y = 100*sin170 + 100*sin50 = 94.0 N. Fr^2 = X^2 + Y^2 = -34.2^2 + 94^2=10006 Fr = 100 N. tanAr = Y/X = 94/-34.2 = -70o = Reference angle. A = -70 + 180 = 110o Fr = 100N[110o].
*October 14, 2013*

**Science**

Incomplete.
*October 14, 2013*

**physics**

d = 2.24m/sin25 = 5.30 m Parallel to the ramp. Work = Fex * d = 290 * 5.30 = 153t J.
*October 14, 2013*

**Physics**

Wc = m * g = 25.4kg * 9.8N/kg = 249 N.= Weight of cart. Fap*cosA-Fk = m * a Fap*cos30.6 -0.7*249 = m*0 = 0 Fap*cos30.6 = 174.3 Fap = 174.3/cos30.6 = 202.5 N. = Force applied. Work = Fap * d = 202.5 * 18.4 = 3726 J.= 3.726 kJ.
*October 13, 2013*

**Math**

Rectangle1: W1 = 6in, L1 = 9in. P1 = 2W1 + 2L1 = 12 + 18 = 30 in. Retangle2: W2 = 8in, L2 = 12in. P2 = 2W + 2L2 = 16 + 24 = 40 in. W1:W2 = 6:8 = 3:4 L1:L2 = 9:12 = 3:4 P1:P2 = 30:40 = 3:4. All of the ratios are equal. Therefore, the rectangles are similar.
*October 13, 2013*

**math**

P = Po + Po*r*t P = 4000 + 4000*(0.07/12)*7 = $4163.33
*October 13, 2013*

**physics**

Fg = m * g = 850kg * 9.8N/kg = 8330 N
*October 13, 2013*

**physics**

Wc=M * g = 660kg * 9.8N/kg = 6468 N. = Weight of the car. Fex - Ff = m*a Fex - 0.31*6468 = m*0 = 0 Fex = 2005 N. = Force exerted.
*October 13, 2013*

**physics**

a = V/t = (1.1m/s)/3.8s = 0.2895 m/s^2. Ws = m * g = 57kg * 9.8N/kg = 558.6 N.= Weight of the sled. Fex - Ff = m * a Fex - 0.06*558.6 = 57*0.2895 Fex - 33.52 = 16.5 Fex = 16.5 + 33.52 = 50.0 N. = Force exerted.
*October 13, 2013*

**Physics**

tanA = 0.3/0.5 = 0.6 A = 31o D = 60/cos31 = 70 m. V = 70/cos31 = 0.583 m/s D = V*t = 70 m. 0.583*t = 70 t = 120.1 s.
*October 13, 2013*

**Physics -URGENT-**

a = 5.7m/s^2[19o] m = 2kg F1 = 17.1N[90o] = 17.1i F2 = ? Fn = m * a = 2 * 5.7[19o] = 11.4N.[19o]= 10.78 + 3.71i. F1 + F2 = Fn = 10.78 + 3.71i 17i + F2 = 10.78 + 3.71i F2=10.78 + 3.71i - 17.1i=10.78 -13.39i F2^2 = 10.78^2 + 13.39^2 = 295.5 F2 = 17.2 N
*October 13, 2013*

**Physics**

See previous post.
*October 12, 2013*

**Physics**

See previous post.
*October 12, 2013*

**Physics**

Vo = 200m/s[30o] Yo = 200*sin30 = 100 m/s. Y^2 = Yo^2 + 2g*h h = (Y^2-Yo^2)/2g h=(0-100^2)/-20 = 500 m. g = -10 m/s^2
*October 12, 2013*

**physics**

d = Vo^2*sin(2A)/g = 100 m. Vo^2*sin(90)/9.8 = 100 0.102Vo^2 = 100 Vo^2 = 980 Vo = 31.3 m/s.
*October 12, 2013*

**physics**

Q1.a = 2.5 * -9.8 = -24.5m/s^2. Q2. V = Vo + g*t = 0 + 9.8*10 = 98 m/s. Q3. V = 0.5g*t = 4.9*10 = 49 m/s. Q4. d = 0.5g*t^2 = 4.9*10^2 = 490 m.
*October 12, 2013*

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