Wednesday

October 26, 2016
Total # Posts: 12,216

**physics**

Do you mean constant velocity? If so, d = V*t, t = d/V.

*February 11, 2016*

**physical science**

d = 0.5a*t^2. d = 10 m, t = 45 s, a = ?.

*February 10, 2016*

**mathematics**

David: X years old. John: x+4 years old. Joe: x-2 years old. x + x+4 + x-2 = 41. Solve for x and add 8 years to John's age.

*February 10, 2016*

**Pysics**

D = -400 + 200[135o] + 100i = -400 - 141.4+141.4i + 100i = -541.4 + 241.4i = 593 km[24o] N. of W.

*February 10, 2016*

**Science**

1. V = Vo + a*t. V = 3.2 m/s, Vo = 1.2 m/s, t = 2.5 s, a = ?. 2. V = Vo + a*t. V = 34 m/s, Vo = 0, t = 2.5 s, a = ?. d = 0.5a*t^2. 3. r = 30m/4.2s. = 4. d = r*t, t = ?.

*February 10, 2016*

**Math**

The simplification process starts inside the expression: ((3x)^4/(6x)^3)^2 = (81x^4/216x^3)^2 = (3x/8)^2 = 9x^2/64.

*February 9, 2016*

**Math**

Y = 3x. 3 = The number of wheels per tricycle. X = The number of tricycles. Y = The total number of wheels to be ordered.

*February 9, 2016*

**math**

15, 5, 3, 0.8, -5.

*February 9, 2016*

**Math**

Po*e^(rt) = 2Po. Divide both sides by Po: e^rt = 2. rt = 0.08t. e^0.08t = 2. 0.08t*Log e = Log 2. 0.08t = Log2/Log e = 0.693 t = 8.7 yrs.

*February 9, 2016*

**math**

a. Tan 24 = h/500, h = ?. b. Tan 27 = (h+L)/500. L = Length of flag = ? h = Ht. of bldg. calculated in part a.

*February 9, 2016*

**physics**

See previous post: Mon, 2-8-16, 7:33 PM.

*February 9, 2016*

**science**

30kW = 30 kJ/s. Work = 30kJ/s * 15s = 450 kJ.

*February 9, 2016*

**Calculus 2**

Sketch the region in the first quadrant enclosed by y=7/x, y=2x, and y=x/2. Decide whether to integrate with respect to x or y. Then find the area of the region.

*February 9, 2016*

**physics**

a. Vr = -100i + 70km[330o] = -100i + 60.6-35i = 60.6 - 135i = 148km[65.8o] S. of E = 24.2o E. of S. = Resultant velocity of the goose. Do you mean 20o W. of S.? If so, Direction = 24.2 + 20 = 44.2o W. of S. b. d = V*t = 1000, t = 1000/V = 1000/148 = 6.76 h.

*February 8, 2016*

**SIMPLE INTEREST**

I = Po*r*t = 5000*0.04*2 = $400. (25/4)% = 6.25%. I = 5000*0.0625*2 = $625. Gain = (625-400)/2yrs. = $112.50 per year.

*February 8, 2016*

**SIMPLE INTEREST**

I = Po*r*t = 0.125Po. Po*0.1*t = 0.125Po. t = 1.25 yrs. = 15 Months.

*February 8, 2016*

**SIMPLE INTEREST**

I = Po*r*t = 1344-1200. Po = 1200, r = 0.06, t = ?.

*February 8, 2016*

**SIMPLE INTEREST**

I = Po*r*t = 1770. r = 0.08 t = (15/2)yrs. = 7.5 yrs. Po = ?.

*February 8, 2016*

**SIMPLE INTEREST**

There are errors in your problem; please make corrections.

*February 8, 2016*

**science**

Sketch: From a point, draw 2 arrows pointing upward and one arrow pointing downward.

*February 8, 2016*

**science**

Fr = 5.3 + 2.2 - 10.7 = -3.2 N. = 3.2 N. downward.

*February 8, 2016*

**Engineering**

Mass = 0.00072kg/cm^3 * 37854cm^3/gal * 5gal. = 136.3 kg.

*February 7, 2016*

**physics**

h = V*t + 0.5g*t^2 = 2 m. V*0.1 + 4.9*0.1^2 = 2. 0.1V = 2-0.049 = 1.95. V = 19.5 m/s at top of the window. V^2 = Vo^2 + 2g*h. V = 19.5 m/s, Vo = 0, g = 9.8 m/s^2, h = ?.

*February 7, 2016*

**Finance**

P = Po(1+r)^n. P = $16,860. r = 5.75%/100 = 0.0575 n = 1Comp./yr. * 6yrs. = 6 Compounding periods. Po = ?.

*February 7, 2016*

**science**

a. h = 0.5g*t^2. h = 20 m., g = 9.8 m/s^2. t = ?. b. d = 10m/s * t. t = Value calculated in part "a".

*February 7, 2016*

**physics**

a. V^2 = Vo^2 + 2g*h = 0. Vo^2 = -2g*h = -(-19.6)*0.18 = 3.53, Vo = 1.88 m/s. b. KE = 0.5M*Vo^2 = 0.5*0.54*10^-6*1.88^2 = 9.54*10^-7 Joules.

*February 7, 2016*

**Physics**

Xo = 2.9 m/s. Tan 43.6 = Y/Xo = Y/2.9. Y = 2.9*Tan 43.6 = 2.76 m/s. V^2 = Vo^2 + 2g*d = 2.76^2. 0 + 19.6d = 7.63, d = 0.389 m. h = 1.14 - 0.389 = 0.751 m. Above the floor.

*February 6, 2016*

**physics**

See previous post: Thu,2-4-16, 11:20 AM.

*February 5, 2016*

**Physics**

Oops! The name is Henry.

*February 4, 2016*

**Math**

A semicircular shape is in a (fills it) rectangle. If the perimeter of the rectangle is 30 cm, fine the perimeter of the semicircular shape.

*January 11, 2016*

**Calculus**

A water tank is made by rotating f(x)=2^x-1 between [0,2] about the y-axis. The water tank is initially full, when a hole is opened at the bottom tip so that the water drains at a rate of 4 unit^3/second. How fast is the height of the water decreasing when the height has ...

*January 8, 2016*

**Calculus**

Okay I didn't know you could do that haha

*January 2, 2016*

**Calculus**

Wait, but how can you let u=x^3 when there is not an x^3 in the equation

*January 2, 2016*

**Calculus**

Last one for me. Evaluate (3x^2)/sqrt(1-x^6) dx I changed sqrt (1-x^6) into 1^(1/2)- x^(3) and let u=1^(1/2)- x^(3) then I got du/dx=3x^2 and subbed dx=du/3x^2 into the equation and got x-(x^4/4) but its not right. Options 7x^3/(3sqrt(1-x^7) + C cos-1(3x) + C sin-1(x^3) + C ...

*January 2, 2016*

**Calculus**

Im think im going to go with B then

*January 2, 2016*

**Calculus**

Okay Thanks. That one confused me.

*January 2, 2016*

**Calculus**

Okay will do. So I'm presuming your saying the answer is B. I think D works.

*January 2, 2016*

**Calculus**

Wait so A is right or is it wrong?

*January 2, 2016*

**Calculus**

Which of the following integrals cannot be evaluated using a simple substitution? I think it is A because if you would substitute there would be nothing left in the equation? Is that right? Options ∫√(x-1) ∫1/√(1-x^2) ∫x/√(1-x^2) ∫&#...

*January 2, 2016*

**Calculus**

Oh shoot I misread my answer. Thanks

*January 2, 2016*

**Calculus**

∫(x^3-x^2)/x^2 I got (x^2)/(2)-x + C but that's not one of the answers Options x - 1 + C (x^2/2)-(x^3/3) + C (x^4-x^3)/4x^2 + C (x^2/2) -x + C

*January 2, 2016*

**Calculus**

Yes Thank you

*January 2, 2016*

**Calculus**

∫((cos^3(x)/(1-sin^(2)) What is the derivative of that integral? I have been trying to use trig identities but can't find one to simplify this equation. I can't find one for (cos^3(x) or (1-sin^(2)) My options -sin(x) + C sin(x) + C (1/4)cos^(4)(x) + C None of ...

*January 2, 2016*

**English**

I chose C

*January 1, 2016*

**Calculus**

I tried to use partial fractions to do it, but it didn't work.

*December 27, 2015*

**Calculus**

Find the integral of 2/((2-x)(x+2)^2)dx.

*December 27, 2015*

**Calculus**

Solve the following problem by separation of variables. T^2y'-t=ty+y+1 Y(1)=0 Y is a function of t.

*December 25, 2015*

**Calculus**

Wait, why is it the integral from 3-5 instead of 0-2?

*December 23, 2015*

**Calculus**

Sorry I forgot the dx after the integral.

*December 23, 2015*

**Calculus**

Find the integral from 0 to 2 of xsqrt(5-sqrt4-x^2)). The hint said to use substitution of u=sqrt(4-x^2), and that I needed one more substitution, but I don't know how to do it.

*December 23, 2015*

**Math**

(Y+1)+4

*December 16, 2015*

**Mathematics**

Show that the root equation (x-a)(x-b)=k^2 are always real numbers

*December 16, 2015*

**Mathematics**

Factorice 16(a-2b)^2-(a+b)^2 leaving your answer in the simplest form

*December 16, 2015*

**math-unit rates**

Jeff hikes 1/4 mile every 2/5 hour. John hikes 1/2 mile every 1/7 hour. A) Who hikes farther in one hour. Show work. B) Who walks faster, Jeff or John. Explain your reasoning

*November 28, 2015*

**science**

I did a physics experiment and now i need help with the matlab fit. can someone tell me how to do this fit in matlab? a1*[sin(a2(x-a3))/(a2(x-a3)]^2*[cos(a4(x-a3))]^2 i have a program that fits a graph to a function i just ask how to write this function.

*November 27, 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*

**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*

**physics**

A quantity that shows magnitude AND direction.

*October 29, 2015*

**geometry**

x^2 + 3x = 180o. x^2 + 3x-180 = 0. Factor it. -180 = -12*15. -12 + 15 = 3 = B. (x-12)(x+15) = 0. X = 12. X = -15. Use positive value of X: X = 12. X^2 = 144o. 3x = 36o.

*October 29, 2015*

**physics**

See Related Questions: Fri, 3-7-14, 4:52 PM.

*October 29, 2015*

**Chemistry**

Methanol, a major industrial feedstock, is made by several catalyzed reactions, such as CO(g) + 2H2(g) ----> CH3OH (l) One concern about using CH3OH as an auto fuel is its oxidation in air to yield formaldehyde, CH2OH(g) which poses a health hazard. Calculate ÄG o at ...

*October 29, 2015*

**physics math science**

Vo = 200m/s[37o]. Xo = 200*Cos37 = 160 m/s. Yo = 200*sin37 = 120 m/s. A. Y = Yo + g*t = 120 + (-9.8)*2 = 100 m/s. = Ver. component of velocity @ 2 s. Tan A = Y/Xo = 100/160 = 0.625. A = 32o. V = Xo/Cos A = 160/Cos32 = 189 m/s[32o]. B. Yf = Yo + g*Tr Yf = 0, g = -9.8m/s^2, Tr...

*October 29, 2015*

**Calculus**

i did. Dv=128pi. But the answer is 8pi/25

*October 28, 2015*

**Calculus**

Use differentials to estimate the amount of paint needed to apply a coat of paint 0.02 cm thick to a sphere with diameter 40 meters. (Recall that the volume of a sphere of radius r is V=(4/3)πr^3. Notice that you are given that dr=0.02.)

*October 28, 2015*

**math**

2 Years ago: Pam: X yrs. old. Sam: 2x/3 yrs. old. 3 yrs. later: Pam: x+3 yrs. old. Sam: 2x/3 + 3 yrs. old 2x/3 + 3 = 3/4(x+3). 2x/3 + 3 = 3x/4+9/4 8x + 36 = 9x + 27. X = 9. So Pam is 3 yrs. older than Sam. In 20 yrs.: x + (x+3) = 69. 2x = 66. X = 33. X+3 = 36. Today: Sam: 33...

*October 28, 2015*

**Physics**

F = 0.119m * 110N./m =

*October 28, 2015*

**Physics**

Wc = M*g = 1400 * 9.8 = 13,720 N. = Normal force, Fn. Fp = mg*sin 0 = 0. = Force parallel to the road. Fk = u*Fn = 0.0889 * 13,720 = 1220 N. a = (Fp-Fk)/M = (0-1220)/1400 = -0.871 m/s^2. Vf^2 = Vo^2 + 2a*d. Vf = 0. a = -0.871 m/s^2. Vo = 21.4 m/s. d = ?.

*October 28, 2015*

**physics**

Wt. = 450cm^3 * 0.998g/cm^3 = 449.1 g. = 0.449 kg of water displaced. M*g = 0.449kg * 9.8N/kg = 4.40 N.

*October 28, 2015*

**SCIENCE\PHYSICS**

Disp. = 0. d = 5 + 5 = 10 m.

*October 28, 2015*

**PHYSICS**

d = 5 + 5 = 10 m.

*October 28, 2015*

**PHYSICS**

Displacement = 0, because it ended at the starting point.

*October 28, 2015*

**PHYSICS**

a. Yf^2 = Yo^2 + 2g*h = 0. Yo^2 = -2g*h = -2*(-9.8)27.5 = 539. Yo = 23.2 m/s. = Vertical component of initial velocity. sin A = Yo/Vo = 23.2/47.5 = 0.48877. A = 29.3o. Xo = Vo*Cos A = 47.5*Cos29.3 = 41.4 m/s = Horizontal component of initial velocity = Total velocity at max ht...

*October 28, 2015*

**physics**

The velocity of the truck must be equal to the hor. component of the airplane's velocity: V = 180*Cos47.

*October 28, 2015*

**Calculus**

Let f(x)=x^4. If a=1 and dx=Δx=1/2, what are Δy and dy?

*October 28, 2015*

**Physics**

Wb = M*g = 200 N., M = 200/g = 200/9.8 = 20.4 kg. sin A = 3/10 = 0.30, A = 17.5o. Fp = 200*sin17.5 = 60 N. Fn = 200*Cos17.5 = 191 N. a. Work = F*d = 120 * 10 = 1200 J. b. Mg*h-0 = Mg*h = 200 * 3 = 600 J. c. Conservation Energy : Change in KE = Change in PE = 600 J. d. Fap-Fp-...

*October 27, 2015*