Friday

May 22, 2015

May 22, 2015

Total # Posts: 10,618

**Physics**

d = Vx*Tf = 3 m. 0.5m/s * Tf = 3 Tf = 6 s. = Fall time. h = 0.5g*Tf^2 = 4.9 * 6^2 = 176.4 m.
*March 6, 2015*

**Physics**

h = 0.5g*t^2 = 7.5 4.9t^2 = 7.5 t^2 = 1.53 t = 1.24 s. = Fall time. d = Vx*t = 15m/s * 1.24s = 18.6 m.
*March 6, 2015*

**physics**

T = M*g + M*a
*March 6, 2015*

**physics**

Vo=1.65 rev/s * 6.28rad/rev=10.362 rad/s V=0.485rev/s * 6.28rad/rev = 3.05 rad/s a. a = (V-Vo)/t
*March 6, 2015*

**Physics**

d = V*t = 4800 m t = 4800/343 = 14 s.
*March 5, 2015*

**Calculus, HELP!!**

1) A rectangular page is to contain 24 square inches of print. The page has to have a 6-inch margin on top and at the bottom and a 1-inch margin on each side. Find the dimensions of the page that minimize the amount of paper used. 2) A cable runs along a wall from C to P at a ...
*March 5, 2015*

**physics**

d1 = V*t = 42m/s * 0.8s = 33.6 m. Head start for the speeder. d2 = d1 + 33.6 m. 20*t + 0.5*a*t^2 = 42*t + 33.6 20t+ 0.5*5*t^2 = 42t + 33.6 2.5t^2 -22t = 33.6 2.5t^2 - 22t - 33.6 = 0 Use Quadratic Formula. t = 10.13 s.
*March 5, 2015*

**Physics**

You gave your answer in miph/s. The problem says "give your answer in mph/s". Which one is correct? 1. a = (V-Vo)/t = (70-0)/3=23.3 miph/s. a = (99.2-0)/4 = 24.8 kmph/s. 2. a = 23.3miph/s * 1.6km/mi = 37.3 kmph/s. = acceleration of the cheetah. a = 24.8 kmph/s = ...
*March 5, 2015*

**Physics**

Eff. = (Output/Input)*100% =(230/420)*100 = 54.8%
*March 4, 2015*

**Physics**

Tension = M*g + M*a
*March 4, 2015*

**physics**

F = 97N - 107N[71.4] Fx = 97 - 107*Cos71.4 = 62.87 N. Fy = 0 - 107*sin71.4 = -101.4 N. a. F^2 = Fx^2 + Fy^2=62.87^2 + (-101.4^2) = 119.3 N. F = N. b. Tan A = Fy/Fx = -101.4/62.87 = -1.61285 A = -58.2o S of E = 301.8o CCW c. 107N[71.4o] - 97
*March 4, 2015*

**Physics**

Fg = M*g = 4 * 9.8 = 39.2 N. = Force of gravity. Fp = 39.2*sin30 = 19.6 N. = Force parallel to the incline. Fn = 39.2*Cos30 = 33.9 N. = Normal force a. W = Fg*d = 39.2 * 10 = 392 J. b. W = Fn*d = 33.9 * 10 = 339 J. c. d. h = d*sin30 = 10*sin30 = 5 m. KE = PE = Mg * h = 39.2 * ...
*March 4, 2015*

**Physics**

M*g = 70*10 = 700 N. = Wt. = Force of gravity(Fg). h = 31steps * 15m/step = 465 m. Work = F*h = Mg * h Joules.
*March 4, 2015*

**Physics**

M*g = 2.2 * 9.8 = 21.56 N. = Wt. of block. Fp = 21.56*sin27.7 = 10.02 N. = Force parallel to incline. Fn = 21.56*Cos27.7 = 19.09 N. = Normal force. Fk = u*Fn = 0.41 * 19.09 = 7.83 N. = Force of kinetic friction. a. a = (Fp-Fk)/M = (10.02-7.83)/2.2 = 0.995 m/s^2 b. L = h/sin27....
*March 3, 2015*

**physics**

M1*V1 + M2*V2 = M1*V + M2*V 5*3 + 5*0 = 5*V + 5*V Solve for v.
*March 3, 2015*

**physics**

V^2 = Vo^2 + 2g*h Vo = 24 m/s g = -9.8 m/s^2 h = 13 m. Solve for V.
*March 3, 2015*

**math**

P = Po(1+r)^n Po = $3,000 r = 1.8%/12/100% = 0.0015. n = 12Comp./yr. * 3yrs. = 36 Compounding periods. Solve for P.
*March 3, 2015*

**physical science**

V^2 = Vo^2 + 2g*d Vo = 0 g = +9.8 m/s^2 d = 80 m. Solve for V.
*March 3, 2015*

**Physics**

M1*V1 + M2*V2 = M1*V3 + M2*V4 M1 = M2? M1*4 + M1*0 = M1*3.46[30o] + M1*V4 Divide both sides by M1: M1*4 = M1*3.46[30] + M1*V4 4 = 3.46[30] + V4 V4 = 4 - 3.46[30] = 4 - 3 - 1.73i = 1-1.73i = 2.0m/s[300o] = Velocity of target ball.
*March 3, 2015*

**physics**

If an object weighs 480 N. on the earth, it's weight on the moon will be 480/6 = 80 N. How did you get 120 N.? The mass on the moon is the same as on earth.
*March 3, 2015*

**trigonometric functions**

h = 100*sin14 =
*February 27, 2015*

**math**

3 thousands, and 3 hundredths.
*February 27, 2015*

**physics**

F-200 = M*a F-200 = 350 * 3 = 1050 F = 1250 N.
*February 27, 2015*

**3rd grade math**

1/3 * 36 = 12.
*February 27, 2015*

**math**

3 thousands, and 3 hundredths.
*February 26, 2015*

**science please help asap**

See Related questions: 2-26-15, 11:06 AM.
*February 26, 2015*

**Math**

2. x + 4 > 6 3. x => 3C 4. x => $15
*February 26, 2015*

**Physics**

F = 392 + 2 = 394 Hz
*February 26, 2015*

**Math**

RQ = 2-(-2) = 4 = Hor. line RP = (2-(-1) = 3 = Ver. line, downward. Tan A = RQ/RP = 4/3 = 1.33333 A = 53.1o
*February 26, 2015*

**maths**

Cos A = 2m/9m.
*February 26, 2015*

**math**

Plate cost $X. A cup cost $2X. A pot cost $2X + 3 x + 2x + 2x+3 = $10.20 Solve for x.
*February 26, 2015*

**physics**

Circumference = pi*2r = 3.14 * 4,180 = 13,132 m. d = V*t d = 13,132 m. V = 233 m/s. Solve for t.
*February 26, 2015*

**Physics mechanics**

d = 60^2/30^2 * 8 = 4 * 8 = 32 m
*February 26, 2015*

**science please help asap**

2. M*g = 490 * 9.8 = 4802 N. = Wt. of the body. Fn = Mg-Fap*sin A = 4802-1200*sin20 = 4392 N = Normal force. Fx-Fs = M*a 1200*Cos20 - Fs = M*0 1128 - Fk = 0 Fk = 1128 N. = Force of kinetic friction u = Fk/Fn = 1128/4392 = 0.257 3A. F = M*a F = 318.1 N. a = 3 n/s^2 M = mass in ...
*February 26, 2015*

**Physics**

Work = F*d = Mg * d. Their wt. and distance was the same; therefore, they did the same amount of work.
*February 26, 2015*

**science**

See previous post.
*February 25, 2015*

**physics**

The force must be in the same direction as the motion(hor.). Work = Fx*d = 0 * 10 = 0
*February 25, 2015*

**Physics**

Work = Fx*d = 200*Cos30 * 20 = Answer in Joules.
*February 25, 2015*

**Math**

(-4,3), (h,k), (6,-5). The center = 1/2 of the total distance: h - (-4) = (6 - (-4))/2 h + 4 = 10/2 = 5 h = 1 k-3 = (-5-3)/2 Solve for k.
*February 25, 2015*

**algebra**

Sarita: X muffins. Clara: X muffins. Joe: X muffins. Clara: x-1 = 14 X = 15 Total = 3x = 3*15 = 45 muffins.
*February 25, 2015*

**algebra**

3x^2 + 3x - 6 = 0 A*C = 3*(-6) = -18 = -3*6 Choose the pair of factors whose sum = B = +3: -3, and 6. 3x^2 + (-3x+6x) - 6 = 0 Form two factorable binomials: (3x^2-3x) + (6x-6) = 0 3x(x-1) + 6(x-1) = 0 (x-1)(3x+6) = 0 (x-1)*3(x+2) = 0 x-1 = 0 X = 1 3(x+2) = 0 Divide by 3: x+2...
*February 25, 2015*

**physics**

V^2 = Vo^2 + 2a*d a = V^2/2d = 87^2/170 = 44.5 m/s^2. M*g = 219,000 N. M = 219000/g = 219000/9.8 = 22,347 kg F = M*a = 22,347 * 44.5 =
*February 25, 2015*

**Physics**

Incomplete.
*February 25, 2015*

**Physics**

V^2 = Vo^2 + 2a*d V = 64.1 m/s Vo = 0 d = 29.2 m. Solve for a. F = M*a M = 35.5 kg Solve for F.
*February 25, 2015*

**physics**

a. V^2 = Vo^2 + 2g*h = 0 Vo^2 = -2g*h = -(-19.6)*1.29 = 25.284 Vo = 5.03 m/s b. 0.5g*t^2 = 1.29 m. 4.9t^2 = 1.29 t^2 = 0.263 Tf = 0.513 s. = Fall Time. Tr = Tf = 0.513 s. = Rise time. Hang time = Tr + Tf = 0.513 + 0.513 = 1.026 s.
*February 25, 2015*

**Algebra**

Y = 3x^2 + 19x - 72 = 0 A*C = 3*(-72) = -216 = -8*27. Sum = 19 (3x^2-8x) + (27x-72) = 0 x(3x-8) + 9(3x-8) = 0 (3x-8)(x+9) = 0 3x-8 = 0 3x = 8 X = 8/3 x+9 = 0 X = -9 Solution: X = -9, and 8/3.
*February 25, 2015*

**Physics**

V = Vo + a*t = Vo = 0 a = 3m/s^2 t = 10 s. Solve for V.
*February 25, 2015*

**physics**

F = M * 3g = 63.6kg * 3*9.8N/kg =
*February 25, 2015*

**Science**

a. PE max = Mg*h = 59*9.8*24 = 13,877 J. b. KE + PE = PE max = 13,877 J.
*February 25, 2015*

**math**

$X in account. x-30 = 3x/4 4x-120 = 3x X = $120
*February 25, 2015*

**physics**

V^2 = Vo^2 + 2a*d a = (V^2-Vo^2)/2d V = 0.63 m/s Vo = 0 d = 0.45 m. Solve for a. F = M*a M = 69 kg Solve for F.
*February 25, 2015*

**Math SO HARD :C**

T + 8 = -20 T = -20-8 = -28o C @ Midnight.
*February 25, 2015*

**physical science**

Correct.
*February 25, 2015*

**Physics**

I = V/R = 9/230 = 0.0391 Amps = 39.1 mA.
*February 25, 2015*

**Algebra 1**

Multiply Eq1 by -2 and add: -10x - 2y = -18 +10x - 7y = 18 Sum: 0 - 9y = 0 Y = 0 In Eq1, replace Y with 0 and solve for X -10x - 2*0 = -18 X = 1.8
*February 24, 2015*

**maths**

X pizzas 4X Drinks 12x + 0.5*4x = 112 Solve for X.
*February 24, 2015*

**physics**

Thank you Damon! I think I understand what you meant when I read your post My triangle was correct though, yes? I just referred to them wrong?
*February 24, 2015*

**physics**

Wait that's not how it's supposed to look. Ok
*February 24, 2015*

**physics**

How do I know which trig function to use? I made my second triangle like this _____ \ | \ | \ | \|
*February 24, 2015*

**physics**

Why did you swap Betas trig functions?
*February 24, 2015*

**physics**

What do you mean, I did indicate on the question that it was west of north?
*February 24, 2015*

**physics**

A golfer takes two putts to sink the ball, one is (81.6 ft, 31.7 degrees N of E) and the other is (3.20 ft, 53.4 degrees W of N). What is the displacement of the single putt that would sink the ball on the first try? Well, what I did was make a diagram of the two vectors, I ...
*February 24, 2015*

**Science**

M*g = 90 N. M*9.8 = 90 M = 9.18 kg Density = 9.18kg/45mL = 0.204 kg/mL Note: A 90-N. object has a mass of 9.18 kg or 9,180 grams.
*February 24, 2015*

**Finance**

V = Vo(1+r)^n r = 5%/365/100% = 0.00013699 = Daily % rate expressed as a decimal. n = 365Comp./yr * 11Yrs = 4015 Compounding periods. V = 10,000(1.00013699)^4015 = $17,332.13
*February 24, 2015*

**Physical science**

Fp = Mg*sin35 = 315 Mg = 315/sin35 = 549 N. = Force of gravity. Fn = Mg*Cos35 = 549*Cos35 = 450 N. = Normal force.
*February 24, 2015*

**Physics**

d = 42m1[135o] - 34mi[270o] X = 42*Cos135 = -29.7 mi Y = 42*sin135 - 34*sin270 = 63.7 mi. Tan A = Y/X = 63.7/-29.7 = -2.14473 A = -65o = 65o N. of W. = 115o, CCW. d = Y/sin A = 63.7/sin 115 = 70.3 mi. d = V*t = 70.3 V = 70.3/t = 70.3/0.5h = 140.6 mi/h
*February 24, 2015*

**Physics**

Vp = -250m/s + i25m/s, Q2. Tan A = Y/X = 25/-250 = -0.10000 A = -5.71o = 5.71o N. of W.= 174.3o,CCW Vp = X/Cos A = -250/Cos(174.3)=251 m/s
*February 23, 2015*

**Physics**

V = Vo + a*t = 31m/s[30o] Vo - 4*4 = 31*Cos 30 + i31*sin 30 Vo - 16 = 26.8 + 15.5i Vo = 42.8 + 15.5i Tan A = Y/X = 15.5/42.8 = 0.36215 A = 19.91o Vo = 42.8/Cos 19.91 = 45.5m/s[19.9o] = Initial velocity.
*February 23, 2015*

**physics**

d = V*t = 2*0.3 km = 0.6 km 216 * t = 0.6 t = (0.6/216) h. t = (0.6/216)h * 3600s./h = 100 s. Note: The sound travels 600m(0.6km).
*February 23, 2015*

**Physics**

1. M*g = Wt. of roller. Fp = Mg*sin 30 = 2500 Mg = 2500/sin 30 = 5000 N. M = 5000/g = 5000/9.8 = 510.2 kg 2. Fn = Mg*Cos 30 = 5000*Cos 30 = 4330 N = Normal force = Force exerted by the surface.
*February 23, 2015*

**Physics**

sin23.3 = h/0.7 h = 0.7*sin 23.3 = 0.277 m. h = 0.5g*t^2 h = 0.277 m. g = 9.8 m/s^2 Solve for t.
*February 23, 2015*

**physics**

Incomplete, and too many errors.
*February 23, 2015*

**Math Vectors**

Vr = 400km/h[200o] + 100km/h[225o] X = 400*Cos200 + 100*Cos225 = -447 km/h Y = 400*sin200 + 100*sin225 = -208 km/h Tan Ar = Y/X = -208/-447 = 0.46532 Ar = 25o = Reference angle. A = 25 + 180 = 205o (Q3). V = X/Cos A = -447/Cos205 = 493 km/h. = Resultant velocity.
*February 22, 2015*

**Math**

a. Range = Vo^2*sin(2A)/g Range = 1200 Ft. Vo = 500 Ft./s. g = 32 Ft/s^2 Solve for A. b. V^2 = Vo^2 + 2g*h h = -Vo^2/2g Vo = 500 Ft./s. g = -32 Ft./s^2 Solve for h
*February 22, 2015*

**math**

Isaiah: X cards. x-x/9 = 560/2 8x/9 = 280 8x = 2520 X = 315 560 - 315 = 245 More than Andy.
*February 22, 2015*

**math**

X = 5 km/h Y = -3 km/h i. Speed = Sqrt(X^2+Y^2) = sqrt(5^2+3^2)= 5.83 km/h = 1.62 m/s. b. Tan A = Y/X = -3/5 = -0.60 A = -31o = 31o S. of E. d = 30m/Cos(-31) = 35 m. = Distance to cross. d = V*t = 35 m. t = 35/V = 35/1.62 = 21.6 s.
*February 21, 2015*

**Physics**

E = 58.0 Volts 1/Ct = 1/C1 + 1/C2 + 1/C3 1/Ct = 1/3.83 + 1/5.89 + 1/12.9 = 0.5084 Ct = 1.97 uF. Qt = Q1 = Q2 = Q3. Qt = Ct*E = 1.97 * 58 = 114.1 uC Q1 = C1*V1 = 114.1 uC V1 = 114.1/3.83 = 29.8 Volts.
*February 20, 2015*

**physics**

Mc = 14 kg = Mass of cart Md = Mass of dog food. d = 0.5a*t^2 = 2.30 m. 0.5a*2.55^2 = 2.3 3.25a = 2.3 a = 0.707 m/s^2. F = M*a M = F/a (Mc+Md) = F/a F = 12 N. a = 0.707 m/s^2 Solve for Md.
*February 20, 2015*

**math**

a. A = 4.1m * 2.2m = 9.02 m^2. A max = (4.1+0.01) * (2.2+0.01) = A min. = (4.1-0.01) * (2.2-0.01) = 8.957 m^2.
*February 20, 2015*

**Math**

X+X = 2x = Total bought. Red Tulips: x-24 Yellow: 4(x-24) 2x-24 Tulips remaining. x-24 + 4(x-24) = 2x-24 x-24 + 4x-96 = 2x-24 3x = 120-24 = 96 X = 32 2x = 64
*February 20, 2015*

**Algebra 2**

W^2 + 5W = 36 W^2 + 5W - 36 = 0
*February 20, 2015*

**physics**

Bill, please clarify your problem by adding the missing words.
*February 19, 2015*

**Physics**

Circumference = pi*Dia = 3.14 * 32.6cm = 102.4 cm = 1.024 m. Vo = 247rev/60s. * 1.024m/rev=4.22 m/s. V = 378rev/60s * 1.024m/rev = 6.45 m/s. V = Vo + a*t V = 6.45 m/s Vo = 4.22 m/s t = 6.54 s. Solve for a. d = Vo*t + 0.5a*t^2
*February 19, 2015*

**physics**

See previous post: Thu, 2-19-15, 6:56 PM.
*February 19, 2015*

**Math**

See previous post: Thu, 10-23-14, 6:36 PM.
*February 19, 2015*

**physics**

A shorter method: R1 = 100 Ohms R2 = 449 Ohms Ri = Internal resistance. V1 = I1*R1 = 4 * 100 = 400 Volts. V2 = I2*R2 = 1.09 * 449 = 489.41 Volts. Ri = (V2-V1)/(I1-I2) = (489.41-400)/(4-1.09) = 30.73 Ohms. E = I1*R1 + I1*Ri = 400 + 122.9 = 522.9 Volts.
*February 19, 2015*

**physics**

E = Battery terminal voltage(e.m.f.). Ri = Internal resistance. R1 = 100 Ohms. R2 = 449 Ohms. I*R1 + I*Ri = E 4*100 + 4*Ri = E Eq1: -E + 4Ri = -400 I*R2 + I*Ri = E 1.09*449 + 1.09*Ri = E Eq2: -E + 1.09Ri = -489.41 Subtract Eq2 from Eq1: Eq1: -E + 4Ri = -400 Eq2: -E + 1.09Ri...
*February 19, 2015*

**physics**

V = 4.93revs/1.47s * 6.28rad/rev = 21.1 rad/s = Angular velocity. V = Vo + a*t V = 21.1 rad/s. Vo = 0 t = 1.47 s. a = rad/s^2 Solve for a.
*February 19, 2015*

**Math 222**

g^2 - 6g - 55 = 0 -55 = 5*(-11) g+5= 0 g+(-11) = 0 g-11 = 0 (g+5)(g-11)= 0
*February 19, 2015*

**physics**

Vo = 20m/s[40o] Xo = 20*Cos40 = 15.32 m/s. Yo = 20*sin40 = 12.86 m/s. a. Y^2 = Yo^2 + 2g*h Y = 0 Yo = 12.86 m/s. g = -9.8 m/s^2 Solve for h. b. Y = Yo + g*Tr Y = 0 Yo = 12.86 m/s. g = -9.8 m/s^2. Solve for Tr.(Rise time or time to reach max. ht.) c. V = Xo + Yi = Xo + 0 = Xo d...
*February 19, 2015*

**physics**

a. V = Vo + a*t V = 25.1 m/s Vo = 0 t = 0.48 s. Solve for a. b. F = M*a M = 910 kg a = Value calculated in part a.
*February 19, 2015*

**Chemistry**

Human bodies maintain their balance (homeostasis) through a series of equilibria. An important equilibrium involves calcium ion because Ca2+ is important for muscle contractions in the heart as well as for strong bones. Bone is a complex tissue consisting of living cells and ...
*February 19, 2015*

**Chemistry**

A 500.0 mL sample of saturated nickel(II) phosphate solution was analyzed spectrophotometrically and found to contain 1.88 × 10-5 g of nickel. (a) Determine the molarity of the nickel(II) phosphate solution. (b) Calculate the solubility product constant, Ksp for nickel(...
*February 19, 2015*

**Chemistry**

The solubility of insoluble substances changes depending on the nature of the solution. Below are two solutions in which Cu(OH)2 is dissolved; in each case, the solubility of Cu(OH)2 in those solutions is not the same as it is in pure water. (a) For each Cu(OH)2 solution below...
*February 19, 2015*

**Physics**

See previous post: 9-16-13, 8:40 PM.
*February 18, 2015*

**physics**

T^2 = 4pi^2*(L/g) L/g = T^2/4pi^2 = 4.17^2/39.5 = 0.440 0.75/g = 0.44 g = 0.75/0.44 = 1.70 m/s^2. It is on the moon!
*February 18, 2015*

**physics**

a. T = 2min/60cycles = 120s/60cycles = 2s/cycles b. F = 1/T = 1cycle/2s. = 0.50 cycles/s. = 0.50 Hz.
*February 18, 2015*

**physical science**

T = 50km * 1h/5km * 60min/h = 600 min.
*February 18, 2015*