Wednesday

February 22, 2017
Total # Posts: 13,198

**Algebra 2**

d = (120+V)T = 490 mi. Eq1: 120T + VT = 490. Eq2: 120T - VT = 350. Sum: 240T = 840. T = 3.5 h. In Eq1, replace T with 3.5 and solve for V.

*November 17, 2015*

**none**

a = 16. b = 16. c = ? c^2 = a^2 + b^2.

*November 17, 2015*

**Physics**

a. -T2*Cos44 + T1*Cos42 = 0. T1*Cos42 = T2*Cos44. T2 = 1.033T1. T2*sin44 + T1*sin42 = -(-608) = 608 N. 1.033T1*sin44 + T1*sin42 = 608. 0.718T1 + 0.669T1 = 608. 1.39T1 = 608. T1 = 438.3 N. b. T2 = 1.033 * 438.3 = 452.8 N.

*November 17, 2015*

**physic**

a. V^2 = Vo^2 + 2g*h Vo = 0. g = 9.8 m/s^2. V = ? b. PE-KE = M*g*h - 0.5M*V^2 = Energy lost. V = 1 m/s.

*November 17, 2015*

**Science**

V = Vo + g*t. Vo = 0. g = 9.8 m/s^2. V = ?

*November 17, 2015*

**Science**

Vf^2 = Vo^2 + 2a*L. Vf = 71 m/s. Vo = 0. a = 1.6 m/s^2. L = ?

*November 17, 2015*

**Physics**

h = 0.5g*t^2 = 1.5 m. 4.9t^2 = 1.5. t^2 = 0.31. t= 0.553 s. = Fall time. Dx = Xo*t = 1.2 m. Xo*0.533 = 1.2 Xo = 2.17 m/s.

*November 16, 2015*

**Math**

Your problem isn't clear; there appears to be errors. Based on my interpretation: 1/T = 1/t1 + 1/t2 + 1/t3. T = ?

*November 16, 2015*

**algebra**

X football cards. 5x baseball cards. x + 5x = 120. X = ?

*November 16, 2015*

**Algebra 1**

W = 30 cm. L/4 + 12 = 30. L/4 = 18 L = 72 cm. h = 20 cm. V = L*W*h.

*November 15, 2015*

**Physics HELP**

D = 4300[49o] + 6500[21o]. X = 4300*Cos49 + 6500*Cos21 = Y = 4300*sin49 + 6500*sin21 = Tan A = Y/X. A = Direction. Magnitude = X/Cos A. or Y/sin A.

*November 15, 2015*

**Physics**

V = 820*sin25 =

*November 15, 2015*

**physics**

D = 15i + 5 -10i - 5 = 5i = 5 km Northwards.

*November 15, 2015*

**physics**

db = 10*Log(Io/Iin.) = 10*Log(28.7/55.1)

*November 15, 2015*

**physics**

R*C < 1*10^-4 s. 1000*C < 1*10^-4. C < 1*10^-7 Farads < 0.10 Microfarads.

*November 15, 2015*

**maths**

P=Po(1+r)^n = 5Po Po = Initial investment. r = (4%/4)/100% = 0.01=Quarterly % rate. n = The number Compounding periods. Po(1.01)^n = 5Po. Divide by Po: 1.01^n = 5. n*Log 1.01 = Log 5. n = Log5/Log1.01 = 162 Compounding periods. 162Comp. * 1yr./4Comp. = 40.5 yrs.

*November 15, 2015*

**PHYSICS**

a. h = ho + (Vf^2-Vo^2)/2g. ho = 60 m. Vf = 0. Vo = 30 m/s. g = -9.8 m/s^2. h = ? b. Vf = Vo + g*Tr. Vf = 0. Vo = 30 m/s. g = -9.8 m/s^2. Tr = Rise time. Tr = ? b. 0.5g*Tf^2 = h(Part a). g = 9.8 m/s^2. Tf = Fall time. Tf = ? Tr + Tf = Time to reach gnd.

*November 15, 2015*

**Physics**

Vf^2 = Vo^2 + 2a*d. Vf = 0. Vo = 50000m/3600s = 13.9 m/s. a = -5m/s^2. d = ?

*November 14, 2015*

**Physics**

Wb = M*g = 3.1 * 9.8 = 30.4 N. Fp = 30.4*sin28 = 14.3 N. = Force parallel to the incline. Fn = 30.4*Cos28 = 26.8 N. = Normal force Fp-Fk = M*a. Fp-Fk = M*0 = 0. Fk = Fp = 14.3 N. = Force of kinetic friction. u = Fk/Fn = 14.3/26.8 = 0.533.

*November 14, 2015*

**Math**

P = Po(1+r)^n = 2Po Po(1.06)^n = 2Po. Divide by Po: (1.06)^n = 2. n*Log 1.06 = Log 2. n = Log 2/Log 1.06 = 11.9 Compounding periods = 11.9 yrs.

*November 14, 2015*

**maths**

See previous post: Sat, 11-14-15r, 3:48 AM.

*November 14, 2015*

**math**

Angle A = X Degrees. Angle B = 2X Degrees. x + 2x = 180o X = 60o = A. 2X = 120o = B. C = A = 60o. The opposite angles are =. D = B = 120o. A+B+C+D = 60 + 120 + 60 + 120 = 360o.

*November 14, 2015*

**physics**

Girl's distance: d2 = 6m/2=3 m from pivot point(center). M1*d1 = M2*d2. 75*d1 = 50*3 = 150. d1 = 2 m. = Boy's distance.

*November 14, 2015*

**physics**

Do you know the angle?

*November 14, 2015*

**physics**

See previous post: Sat, 11-14-15,

*November 14, 2015*

**physics**

a. AM band: L1 = V/F = 3*10^8/5.5*10^5 = L2 = 3*10^8/1.585*10^6 b. FM band: L1 = V/F = 3*10^8/8.8*10^7 = L2 = 3*10^8/1.08*10^8 =

*November 14, 2015*

**Physics**

V = Vo + a*t. Vo = 60,000m/3600s = 16.7 m/s. V = 90,000/3600s. = 25 m/s. t = ?.

*November 14, 2015*

**physics**

d = 5.5rev * 6.28rad/rev = 34.6 radians. V = 34.6rad./3s. = 11.5 rad/s.

*November 14, 2015*

**Physics**

d1 = r*t = 160 km. 80*t = 160. t1 = 2 hrs. d2 = r*t = 160 km. 100*t = 160. t2 = 1.6 hrs. r(avg.) = (d1+d2)/(t1+t2) = 320/3.6 = 88.9 km/hr.

*November 14, 2015*

**maths**

4/4 - (1/4+1/4) = 4/4 - 2/4 = 2/4 = 1/2 Left. 1/2 - 1/3 = 3/6 - 2/6 = 1/6 Left for wife. (1/6)/(2/6) * 100,000 = 1/2 * 100,000 = 50,000 = Wife's amount.

*November 14, 2015*

**Math**

A = X Degrees. B = (4x+20) Degrees. x + (4x+20) = 90o. X = ?

*November 14, 2015*

**Math**

Correction: Math-99Henry. should be Math Henry.

*November 13, 2015*

**High school /physic**

Vf = Vo + g*t. Vf^2 = Vo^2 + 2g*h.

*November 13, 2015*

**Math**

See previous post: Thu, 11-12-15, 11:06 PM.

*November 13, 2015*

**Math**

P = Income-Expense=20x-((20x/2)+18)=200. 20x - (10x+18) = 200. 20x - 10x - 18 = 200. 10x = 218. X = 21.8 or 22 Copies.

*November 13, 2015*

**University of North Dakota**

Correction: Change 49.5 to 495.

*November 13, 2015*

**University of North Dakota**

Acc. #1: Po1 = $X @ 9.5%. Acc. #2: Po2 = $(33,000-X) @ 1.5%. Po1*r1*t = Po2*r2*t. X*0.095*1 = (33,000-X)*0.015*1. 0.095x = 49.5 - 0.015x. 0.11x = 495. X = $4500. 33000-X = 33000-4500 == $28,500.

*November 13, 2015*

**Math**

d = 16t^2 = 1551 Ft. t^2 = 96.9375. t = 9.8 s. V = 64h?? 62

*November 12, 2015*

**math**

V = 0.3125 * 18 * 15 = in^3. Wt. = V*D = V * 0.698 = The surface area(As) is the area of the 6 sides: As = 2*W*h + 2*L*h + 2*L*W. L = 18 1n. W = 15 in. h = 0.3125 in.

*November 12, 2015*

**Math homework**

6/6-1/6 = 5/6 = Remainder. 5/6-2/5 = 25/30-12/30 = 13/30 Left.

*November 12, 2015*

**algebra**

Y = x^2+5x-36 = 0 -36 = -4*9, -4+9 = 5 = B. (x-4)(x+9) = 0.

*November 12, 2015*

**PHYSICS**

D = 350rev/60s * 0.64s * 6.28rad/rev =

*November 12, 2015*

**PHYSICS**

Do you think we might need to know the angles?

*November 12, 2015*

**Physics**

V^2 = Vo^2 + 2a*d = 0. a = -(Vo^2)/2d. It will be negative.

*November 11, 2015*

**Physics**

C = pi*2r = 3.14 * 2*0.98 = 6.15 m. 0.44rev/s. * 6.15m/rev = 2.71 m/s. = Tangential speed.

*November 11, 2015*

**physics**

Wo = M*g = 2 * 9.8 = 19.6 N. Fn = 19.6-20*sin20 = Normal force. Fk = u*Fn = Force of kinetic friction. Net force = 20*Cos20 - Fk.

*November 11, 2015*

**Pre-Alegebra**

3. Irrational. 4. D^2 = 15^2 + 8^2, D = 17. 5. You can test each choice by taking the cube root or raising it to the 1/3 power: 100^(1/3) = 4.64 125^(1/3) = 5 = A perfect cube. 6. Whole number/Integer. 7. 9/10. 8. Sqrt(35) = 5.92 In. Cut the 6-in. piece. 10. Riley: Sqrt(36) = ...

*November 11, 2015*

**Physics**

V^2 = Vo^2 + 2g*h. Vo = 0. g = 9.8 m/s^2. h = 2.1 m. V = ?

*November 11, 2015*

**physics**

Vf^2 = Vo^2 + 2g*h = 0. h = -Vo^2/2g + 1.5 = Meters above gnd. Vo = 20 m/s. g = -9.8 m/s^2.

*November 11, 2015*

**nwfsc**

V = I * R = 20 * 7 = 140 Volts. R = V/I = 140/14 = 10 Ohms.

*November 10, 2015*

**Math**

Libby: $60. Jess: 3/4 * 60 = $45. Stephanie: 1/3 * 45 = $15. Total:

*November 10, 2015*

**Math**

P(1, 2). Slope = 3. (1, 2), (x, y). m = (y-2)/(x-1) = 3. (y-2) = 3(x-1).

*November 9, 2015*

**math**

I've solved several of your problems. Where is the end?

*November 9, 2015*

**math**

Same procedure as your previous post.

*November 9, 2015*

**math**

I = Po*r*t = $1200. r = (18%/12)/100% = 0.015 = Monthly % rate expressed as a decimal. t = 1 Mo. Po*0.015*1 = 1200. Po = $80,000.

*November 9, 2015*

**math**

P = Po + Po*r*t = 2Po. Po + Po*0.1*t = 2Po Divide by Po: 1 + 0.1t = 2. 0.1t = 1. t = 10 Years.

*November 9, 2015*

**math**

I = Po*r*t. I = $3600. Po = $20,000. r = 0.12. t = ?.

*November 9, 2015*

**math**

P = Po + Po*r*t.

*November 9, 2015*

**Physics**

a. Vo = 60000m/3600s. = 16.7 m/s. Vf = 40000m./3600s. = 11.1 m/s. b. a = (Vf-Vo)/t = (11.1-16.7)/8 = -0.699 m/s^2.

*November 9, 2015*

**AP Physics**

Wb = M*g = 55 * 9.8 = 539 N. Fp = 539*sin40 = 347 N. = Force parallel to the ramp. Fn = 539*Cos40 = 413 N. = Normal force. Fp-Fk = M*a. 347-Fk = M*0 = 0. Fk = 347 N. = Force of kinetic friction. u = Fk/Fn.

*November 8, 2015*

**physics**

180N[W60oN] + [140N[90o] + 180N[E60oN]+ Ws = 0. Ws=-(-180*Cos60+180*sin60+140i+180*Cos60 +180*sin60) = -(155.9i+140i+155.9i) = -452i = -452 = 452 N. Downward. = Wt. of the sign. The horizontal components cancelled: 180*Cos60 - 180*Cos60 = 0.

*November 8, 2015*

**physics**

a = M1/M2 * a1 = 2.9/6.2 * 2.7 = 1.26 m/s^2.

*November 8, 2015*

**Science**

Mass = 200Lbs * 0.454kg/Lb = 90.8 kg. Wb = M*g = 90.8 * 9.8 = 889.84 N. = Normal force(Fn). a = 10Ft/s^2 * 1m/3.3Ft = 3.03 m/s^2. Fk = u*Fn = 0.25 * 889.84 = 222.5 N. = Force of kinetic friction. Fap-Fk = M*a. Fap = Applied or required force. Fap = ?.

*November 8, 2015*

**physics**

See previous pose: Sat, 11-7 15, 6:23 PM.

*November 8, 2015*

**physics**

F1 + F2 + F3 = 0. F3 = -(F1+F2) F3 = -(18[E60oN]+6.5[E45oS]) = -(18*Cos60+18*sin60 +6.5*Cos45+6.5*sin45 = -(9+15.6i + 4.6-4.6i) = -(13.6+11i) = -13.6 - 11i = 21.6N.[39o] Below the negative X-axis. f4

*November 8, 2015*

**ap physics**

Incomplete.

*November 8, 2015*

**physics**

Vf^2 = Vo^2 + 2a*d.

*November 7, 2015*

**physics**

V = Vo + a*t = 41.1m/s[26.5o]. 3.87[40.3o] + a*8.35 = 41.1[26.5]. 2.95+2.50i + a*8.35 = 36.8 + 18.3i. a*8.35 = 36.8 + 18.3i - 2.95 - 2.50i. a*8.35 = 33.9 + 15.8i = 37.4m/s[25o]. a = 4.48m/s^2[25o], CCW from +X-axis.

*November 7, 2015*

**physics**

Vf = Vo + a*t = 59.1m/s[43o]. Vo + 2.1[31.7o]*7.75 = 59.1[43]. Vo + 16.3[31.7o = 59.1*Cos43+59.1*sin43. Vo+16.3*Cos31.7+16.3*sin31.7=43.2+40.3i. Vo + 13.9 + 8.6i = 43.2 + 40.3i. Vo=43.2 + 40.3i - 13.9 - 8.6i=29.3+31.7i Vo = 43.2m/s[47.3o], CCW from +X-axis.

*November 7, 2015*

**physics**

P = E*I = 1.0 W. 1.58I = 1.0 I = 0.633A. A*h = 1. 0.633*h = 1. h = 1.58 Hours.

*November 7, 2015*

**Calculus**

Find the Absolute Maximum and Absolute Minimum of f on (0,3]. f(x)=(x^3-4x^2+7x)/x Multiple choice question I know the minimum is (2,3) but the maximum is either nothing or (0,7) but I can't tell which one

*November 7, 2015*

**science**

Velocity in kg/h???.

*November 7, 2015*

**physics**

Wc = M*g = 330 * 9.8 = 3234 N. = Normal force, Fn. Fap = 410 + 240 = 650 N. = Force applied. Fap-Fk = M*a. Fap-Fk = M*0 = 0. Fk = Fap = 650 N. = Force of kinetic friction. u = Fk/Fn.

*November 6, 2015*

**Physics**

V = Vo + g*T. Vo = 0. g = 10 m/s^2. h = ho - 0.5g*Tf^2 = 0. 5Tf^2 = 80. Tf^2 = 16. Tf = 4 s. = Fall time. Use T in the range of 0 to 4 seconds. (T,V,h). (0,0,80). (1,10,75). (2,20,60). (3,30,35). (4,40,0).

*November 6, 2015*

**math**

1. 6x4 in., P = 2*6 + 2*4 = 20 in. 2. 6*2 in., P = 2*6 + 2*2 = 16 in. 3. 4x2 in., P = 2*4 + 2*2 = 12 in. =

*November 5, 2015*

**Physics**

Units of time are seconds, minutes, and hours. Vf = Vo + a*t = 0. t = -Vo/a = -22/-6.1 = 3.61 s.

*November 5, 2015*

**Precalc**

a. P = Po(1+r)^n Po = $60,000. r = (4%/4)/100% = 0.01 = Quarterly % rate expressed as a decimal. n = 4Comp./yr. * 10yrs. = 40 Compounding periods. P = ? c. Same procedure as a.

*November 5, 2015*

**physics**

Vf = Vo + a*t = 3 + 1*5 = 8 m/s. d = Vo*t + 0.5a*t^2.

*November 5, 2015*

**universitu**

See Related Questions: Sun, 2-17-13, 5:09 AM.

*November 5, 2015*

**Calculus**

use tangent line approximation (linear approximation) to estimate The cube root of 1234 to 3 decimal places. Hint: the equation should be y=f'(x0)(x-x0)+f(x0) 11^3=1331 can be easily computed using binomial theorem. I used linear approximation and got 10.733, but it is not...

*November 4, 2015*

**Physics**

a. 0.5g*t^2 = 4780. 4.9t^2 = 4780. t^2 = 975.5 t = 31.2 s. Dx = 175m/s * 31.2s = 5465.8 m.

*November 3, 2015*

**math**

2. X = -30 km/h = velocity of the wind. Y = -295 km/h.=velocity of the aircraft. Q3. tan A = y/x = -295/-30 = 9.83333. A = 84.2o S. of W. = direction. Vr = y/sin A=-295/-sin84.2 = 296.5 km/h.

*November 3, 2015*

**physics**

Vf^2 = Vo^2 + 2g*h. g = 9.8 m/s^2.

*November 3, 2015*

**Science**

10cm3 * 10.5g/cm^3 = wt. in grams. mass = g/1000 = kilograms.

*November 2, 2015*

**physics**

140rev/60s * 20s =

*November 2, 2015*

**science**

T1*Cos26.5 - T2*Cos49.5 = 0 T1*Cos26.5 = T2*co49.5. T1 = 0.73T2. T1*sin26.5 + T2*sin49.5 = 155. Replace T1 with 0.73T2: 0.73T2*sin26.5 + T2*sin49.5 = 155. 0.324T2 + 0.760T2 = 155. 1.084T2 = 155. T2 = 143 N. T1 = 0.73*143 = 104 N.

*November 1, 2015*

**Physics**

Work = F*d = 23*Cos39 * 8 =

*November 1, 2015*

**physics**

Fs = M*g = 14 * 9.8 = 137 N. Fp = 137*sin 0 = 0 = Force parallel to the gnd. Fn = 137*Cos 0 - 25*sin30 = 124.5 N. = Normal Force. Fk = u*Fn = Force of kinetic friction. a = (25*Cos30-Fp-Fk)/M. Vf^2 = Vo^2 + 2a*d Vo = 1 m/s. d = 18 m. Vf = ?

*November 1, 2015*

**Physics**

See Relate Questions: Tue, 2-7-12, 1:11 AM.

*November 1, 2015*

**science**

Vf = Vo + g*Tr = 0. 24.5 + (-9.8)Tr = 0. -9.8Tr = 24.5 Tr = 2.5 s. = Rise time. Tf1 = Tr = 2.5 s = Time to fall back to roof. h = Vo*t + 4.9*t^2 = 24 m. 24.5*t + 4.9t*2 = 24. 4.9t^2 + 24.5t -24 = 0. Use Quad. Formula. t = 0.839 s. = Time to fall from top of roof to gnd. T = Tr...

*November 1, 2015*

**physics**

Fb = M*g = 13 * 9.8 = 127.4 N. Fp = 127.4*sin 0 = 0. = Force parallel to the floor. Fn = 127.4 - 86.4*sin64. = Normal force. Fk = u*Fn = Force of kinetic friction. a = (F*Cos64-Fp-Fk)/M.

*November 1, 2015*

**physics**

F1 = 2123 N. F2 = 1930 N. M = 1245 kg. a = (F1-F2)/M.

*November 1, 2015*

**Physics**

Vo = 90,000m/3600s = 25 m/s. d1 = Vo*t = 25m/s * 0.75s. = 18.75 m. d2 = 40 - 18.75 = 21.25 m. = Required stopping distance. Vf^2 = Vo^2 + 2a*d. Vf = 0. Vo = 25 m/s. a = -10 m/s^2. If d is => 21.25 m, the car will hit the barrier.

*October 31, 2015*

**physics**

4. Incomplete. Vo = 35m/s[33o]. Xo = 35*Cos33 = 29.4 m/s. Yo = 35*sin33 = 19.1 m/s. 5A. Yf^2 = Yo^2 + 2g*h. Yf = 0. g = -9.8 m/s^2. h = ? B. Dx = Vo^2*sin(2A)/g. A = 33o. g = +9.8 m/s^2. Dx = ?

*October 31, 2015*

**SPR,PHYSICS**

Vs = Db/Dw * Vb = 2/3 * Vb = 2Vb/3. Db/Dw * Vb = 2Vb/3. Db/Dw = 2/3 = 0.667. Db=0.667Dw = 0.667 * 0.998=0.665 g/cm^3. = Density of the block. Notes: Vs = Volume submerged. Db = Density of the block. Dw = Density of water. Vb = Volume of the block.

*October 30, 2015*

**force**

Wb = M*g = 10*9.8 = 98 N. Fp = 98*sin 0 = 0 = Force parallel to the surface. Fn = 98*Cos 0 - 40*sin30 = 78 N. = Normal force. Fk = u*Fn = 0.3 * 78 = 23.4 N. = Force of kinetic friction. a=(Fap*Cos30-Fp-Fk)/M=(34.6-0-23.4)/10 = 1.12 m/s^2.

*October 30, 2015*

**Physics**

I had this same problem... θ > arctan(μs) is the answer, you're welcome fam.

*October 29, 2015*

**math**

d1 = 10km/h * (20/60)h = 3.33 km., N. d2 = 5km/h * (35/60)h=2.92 km, NE.(45o)= 2.06 + 2.06i. Disp.=2.06 + 2.06i + 3.33i=2.06 + 5.39i = sqrt(2.06^2 + 5.39^2)

*October 29, 2015*

**physics**

Disp. = 7m[90o] + 9m[E45oN] + 7m[W14oS] X = 9*Cos45 + (-7*Cos14) = -0.428 m. Y = 7 + 9*sin45 + (-7*sin14) = 11.7 m. Q2. Tan A = Y/X = 11.7/-0.428 = -27.26754. A = -87.9o = 87.9o N. of W. = Direction. Disp. = Y/sin A = 11.7/sin87.9 = 11.71 m

*October 29, 2015*

**physics**

Disp. = 7m[90o] + 9m[E45oN] + 7m[S76oW]. X = 9*Cos45 - 7*Cos76 = 1.84 m. Y = 7 + 9*sin45 - 7*sin76 = 6.57 m. Q1. Tan A = Y/X = 6.57/1.84 = 3.57168. A = 74.4o N. of E. = Direction. Disp. = Y/sin A = 6.57/sin74.4 = 6.82 m

*October 29, 2015*