Posts by Henry
Total # Posts: 14,355

Math
Add point C at bottom of bldg. AB = 11 m. Point D is top of bldg. BD is hyp. of triangle BCD. h = (BC+11)Tan50 = BC*Tan63. (BC+11)Tan50 = BC*Tan63. Divide both sides by tan50: BC+11 = 1.65BC BC = 16.9 m. = Hor. leg of rt. triangle. h = BC*Tan63 = 16.9*Tan63 = 33.2 m. = Ver. ... 
math
(3/4)/(3/5) = x/1. 3/4 * 5/3 = x, X = 15/12 = 5/4. 
Physics
V^2 = Vo^2 + 2g*h = 0 + 19.6*2.5 = 49, V = 7 m/s. 
Maths
5x/(x^2+1) <= x. Multiply both sides by x^2 + 1: 5x<= x(x^2+1), 5 <= x^2 + 1, 4 <= x^2 2 <= X. X=> 2. 
mathematics
A1 = L * W . A2 = 1.1W * 1.2*L = 1.32LW. A2/A1 = 1.32LW/LW = 1.32 = 132%. 132%  100% = 32% Increase. 
mathematics
Let width = 2 Ft. Length = 4 Ft.. Area = 2 * 4 = 8 Ft^2. Width = 1.1 * 2 = 2.2 Ft. Length = 1.2 * 4 = 4.8 Ft. Area = L * W = 4.8 * 2.2 = 10.56 Ft.^2. 10.56/8 = 1.32 = 132%. Increase = 132%100% = 32%. 
math
Do you mean 5%/yr.? If so: P = Po + Po*r*t. P = 500,000 + 500,000*(0.05/12)*8 = 
math
The dog that eats only 1/8 Lbs/wk is on a diet!1 LOL. 
math
4 1/2 + 1/8 = 9/2 + 1/8 = 36/8 + 1/8 = 37/8 = 4 5/8 Lbs/wk. 
Math
d = r * t = 90ft/s * 25s. 
Maths
A person stands in front of a cylindrical water tank and has a viewing angle of 27 degrees to the sides of the tank. What percentage of the circumference of the tank can they see? 
Math
1. A = 100Ft^2. L = sqrt(100)= 10Ft. = Length of each side. 10Ft/side * 4sides = 40 Ft. 3. A perfect square is a number whose square root is a whole number: 9, 25, 144 and 36 are perfect squares, because their square root is a whole number. 4. sqrt(625) = 25 Ft./side. 5. ... 
Physics
post 
Physics
2. I max = E/R = 6.5/116.6 = 0.392A. I min = 0.01 * 0.392 = 0.00392A. Imax/e^(t/T) = Imin. e^(t/T) = Imax/Imin = 0.392/0.00392 = 99.89, t/T = 4.60. T = L/R = 0.0696/16.6 = 0.004193 = LR time constant. t/0.004193 = 4.60. t = ? 
Physics
1. VR = 6.50 Volts(t = 0). VR = I*R = 0.235 * 16.6 = 3.901 Volts(t = 2.14 mS). 6.5/e^(t/T) = 3.90, e^(t/T) = 6.50/3.90 = 1.666, t/T = 0.5104, T = t/0.5104 = 0.00214/0.5104 = 0.004193. T = L/R. 0.004193 = L/16.6, L = 0.0696 henrys = 69.6 mH. 
Algebra
X gal. of blue. 3x/2 = 1.5x gal. of yel. x + 1.5x = 12. 
Math
A = 1m * 20m = 20m^2. 
math
P(4,3), m = A/B = 2/5 = 2/5. Y = mx+b. 3 = (2/5)(4) + b, b = ? Plug the calculated value of m and b into the above equation. 
Algebra
5qts * 1gal./4qts * 1/60s = 0.0833 gal./s. T = 65,000gal. * 1s/0.0833gal * 1h/3600s = 216.67 Hours. T = 216.67h * 1day/24h * 1wk/7day = Weeks. 
math
Bulbs = 2^(n+1). n = The number of years. In the 10th year: Bulbs = 2^(10+1) = 2^11. bulbs = 2^n+1) 
math
D = 7km[120o] + 9km[180o]. X = 7*sin120 + 9*sin180 = 6.06 km. Y = 7*Cos120 * 9*Cos180 = 12.5 km. D = 6.06  12.5i = 13.9km[25.9o] = 13.9km[25.9o] S. of E. = 13.9km[103.5o] CW(bearing). Tan A = X/Y. 
Math
What is the compounding frequency? Is it daily, monthly, or annually? We can't do compounded int. without knowing the frequency. 
Circuits 2
Given: R1 = 30 Ohms. I1 = 4A. Ic = 6A = Current through coil. I = 8A = Total current. E = I1*R1 = 4 * 30 = 120 Volts. = Applied voltage = Voltage across R1. WL = E/Ic = 120/6 = 20 Ohms. = Inductive reactance. L = 20/W = 20/377 = 0.053 henrys. Note: W = 2pi*F = 6.28 * 60 = 377.. 
Maths
t^2 + k^2 = 9 2t^2  5k^2 = 6 Solve the simultaneous equations Thanks 
Algebra
$X/gal. at beginning of July. $1.12X/gal. after July increase. Aug: 0.85 * $1.12X/gal. = $0.952X/gal.. 0.952X = 2.29, X = $2.41/gal. 
science
Procedure, and Objective. 
math
One side of a rectangle is five times as long as the other side. If the perimeter is 72 meters, what is the length of the shorter side? ___ meters 
math
Width = W. Length = 3W. 2W + 2L = 320. 2W + 2*3W = 320, W = 40 Ft. = Width. Length = 3W = 3*40 = 120 Ft. Since the barn forms one end of the rectangle, we only need W + 2L: W + 2L = 40 + 2*120 = 280 Ft. 
math
A farmer wishes to fence a rectangular area behind his barn. The barn forms one end of the rectangle and the length of the rectangle is three times the width. How many linear feet of fence must he buy if the perimeter of the rectangle is 320 feet? The possible solutions are ... 
math
2 Parts. 
math
In how many regions (parts) do three lines in general position divide a plane? 
maths
P = Po(1+r)^t. Po = $2873. r = 0.12/12mo. = 0.01/mo. t = 12mo/yr. * 4yts = 48 mo. 
Trig
Vp + 80[45o] = 600[45o]. Vp + 80*sin45 +i80*Cos45 = 600*sin45 + i600*Cos45, Vp + 56.6 + i56.6 = 424.3 + i424.3, Vp = 367.7 + i367.7 = 520 km/h[45o]. = Air speed and heading of the plane. Note: If the wind is blowing from southwest, the bearing is 225o Not 315o. 
Trig
Vp + 80km/h[315] = 600[45o]. Vp + 80*sin315 + i80*Cos315 = 600*sin45 + i600*Cos45, Vp  56.6 + i56.6 = 424.3 + i424.3, Vp = 480.9 + i367.7 = 605.4km/h[52.6o] = Air speed and heading of the plane. 
physics
1.453km/s = 1,453 m/s. V^2 = Vo^2 + 2g*h. 0 = 1453^2  3.24h, h = ? 
physics
Vo = 32.5m/s[33o]. Xo = 32.5*Cos33 = 27.5m/s = Hor. component of initial velocity. Y = 0 = Ver. component of velocity at max. ht.(apex). V = Xo + Yi = Xo + 0 = Xo = 27.3 m/s = Velocity at max. ht. KE = 0.5M*V^2 = 0.5*0.41*27.3^2 = 
Physics
V = Vo + a*t. 0 = 70 + a*2, "a" will be negative. . 
math
Used 1/5 of a box. Remainder = 5/51/5 = 4/5 box. Used 3/4 * 4/5 = 12/20 = 3/5 box to make bread. Remainder = 4/5  3/5 = 1/5 box. (1/5)/5 = 1/5 * 1/5 =1/25 box in each container. 
Trigonometry
All angles are measured CW from +Yaxis. Vb + 9[312o] = 24km[42o]. Vb + 9*sin312+i9*Cos312 = 24*sin42 + i24*Cos42, Vb  6.69 + 6.02i = 16.1 + 17.8i, Vb = 22.79 + 11.78i = 25.7km[62.7o]. = Velocity and direction of the blimp(gnd. speed). Tan A = X/Y = 22.79/11.78. Drift = 62.7... 
Science
Divide change in distance by the change in time: (25555)/(10:3210:30) = 200m/2min. = 100m/min. = 1.67m/s. 
Maths
Brendan has a rectangular paved area in his backyard. If the length and breadth were increased by the same percentage and the area increases by 21%, what is the percentage increase of the length and breadth? 
Circuits2
zR = 0+j3. Did you mean zR = 3+j0?. The j operator is used with inductors and capacitors to indicate a 90o phase difference. 
Trigonometry
Vp = 650[255o] Correction: Since the wind is blowing FROM 320o, the heading is 140o. Vp = 650mi/h[255o] + 28mi/h[140o]. X = 650*sin255 + 28*sin140 = 609.9 mi/h. Y = 650*Cos255 + 28*Cos140 = 189.7 mi/h. Vp = 609.9  189.7i = 639mi/h[72.7o] W. of S. = 639mi/h[252.7o] CW. Tan ... 
Trigonometry
All angles are measured CW from +Yaxis. Vp = 650[255o] + 28[320o]. X = 650*sin255 + 28*sin320 = Y = 650*Cos255 + 28*Cos320 = Vp = sqrt(X^2+Y^2). = Velocity of the plane(gnd. speed). Direction: Tan A = X/Y. t 
Trigonometry
post it. 
Trigonometry
Vr = X + Yi = 2  5i = 5.39km/h[68.2o] = 5.39km/h[68.2o]S. of E. = Resultant velocity and Direction. 
Trigonometry
Note: 33.7o W. of S. = 214o CW from +Yaxis. 
Trigonometry
Vr = 550mi/h[225o] + 110mi/h[135o]. X = 550*sin225 + 110*sin135 = 311.1 mi/h. Y = 550*Cos225 + 110*Cos135 = 466.7 mi/h. Vr = 311.1  466.7i = 561mi/h[33.7o] = 561mi/h[214o]CW(Bearing) = Resultant velocity and Direction. Drift = 225214 = 
Circuits2
Given: zL = 3+j4 Ohms. zC = 4j4 Ohms. zR = 3+j0? Ohms. (3+j4)(4j4)/(3+j4+4j4) = (12j12+j16+16)/7 = (28+j4)/7=4+j4/7 = zL in parallel with zC. Z = 3(4+j4/7)/(3+4+j4/7) = (12+j12/7/(7+j4/7) = 12+j12/(7+j4) = 17[45o]/8.06[29.7 = 2.1Ohms[15.3o] Power Factor = Cos15.3 = 0.96. 
Trigonometry
580[128o] + Vw = 500[140o]. 580*sin128+i580*Cos128 + Vw = 500*sin140+i500*Cos140. 457357.1i + Vw = 321.4383i, Vw = 321.4457383i+357.1i = 135.6  25.9i = 138mi/h[79.2o]Cw from +Yaxis. = Velocity of the wind. NOTE: For clockwise rotation from +Yaxis(Bearing), the X... 
algebra
0.03*5000 + 0.04(N5000) = 320. 150 + 0.04N  200 = 320, 0.04N = 370, N = $9250 = Total sales. 
algebra 1
sqrt(5x)(sqrt(x))5sqrt(5) = (sqrt(5))x  5sqrt(5) = (sqrt(5))(x5). 
Math
6. d = V*T. 720 = 1200*T. Solve for T and Convert from hours to minutes. 10. P = Po(1+r)^t. r = 0.04/12 = 0.00333/mo. t = 5yrs. * 12mo/yr. = 60 mo. Po = $520. 
Math
Today: Daughter's age = X years. Mother's age = 2X years. x + 2x = 56 + 2 + 2. Each is 2 years older. 
Physics
a. WL = V/f = 340/200 Meters. b. L = WL = V/f = 340/200 meters. 
physics/electrical circuits
The answer is "A". 
physics/electrical circuits
1/Req. = 5/R. 1/20 = 5/R, 
physics/electrical circuits
Given: L = 50 cm = 0.50 m. A = 1mm^2 = 10^6 m^2. E = 2 Volts. I = 2 Amps. R = E/I = 2/2 = 1 Ohm. R = p*L/A. 1 = p*0.5/10^6, p = 2*10^6 Ohmmeters = Resistivity. 
physics/electrical circuits
1/Req. = 11/33k. Req. = 33k/11 = 3k = Equivalent resistor. 
Physics
Correction: V3 = (4(500.45)  27)/(50.45), V3 = (198.2  27)/50.45 = 3.39 m/s. b. a = (V4V2)/0.021 
Physics
a. Given: M1 = 50kg, V1 = 4 m/s. M2 = 0.45 kg, V2 = 30 m/s. V3 = Velocity of M1 after colliding. V4 = Velocity of M2 after colliding. Momentum before = Momentum after M1*V1 + M2*V2 = M1*V3 + M2*V4. 50*4 + 0.45*(30) = 50*V3 + 0.45*V4. Eq1: 50V3 + 0.45V4 = 186.5. V3 = (V1(M1... 
physics
rate = d/T = 100/(1+1.5) = 
Physics
2. FpFk = M*a. 0.6Mg  u*0.8Mg = M*a, Divide both sides by M: 0.6g  ug = a, 0.6*9.8  9.8u = a, 9.8u = a  5.88, u = 0.1a + 0.6. We have 1 Eq and 2 unknowns. Therefore, we cannot calculate "a". 
Physics
1. Mg = Wt. of box. Fp = Mg*sin A = Mg*(6/10) = 0.6Mg = Force parallel to ramp. X^2 + 6^2 = 10^2, X = 8. Fn = Mg*CosA = Mg*(8/10) = 0.8Mg = Normal force. Fs = u*Fn = u*0.8Mg = Force of static friction. FpFs = M*a. 0.6Mgu*0.8Mg = M*0 = 0, Divide both sides by Mg: 0.6  0.8u... 
physics
Fnet = M*a. F2F1 = M*a, 125120 = 10a, 
Physics
post it. 
Physics
F1+F2 = 10 + 5[60]. F1+F2 = 10+5*Cos60 + i5*sin60, F1+F2 = 12.5 + 4.33i. = 13.2N[19.1o]N. of E. F3 is equal in magnitude to F1+F2 but 180o out of phase(opposite). F3 = 13.2N[19.1+180] = 13.2N[199.1]CCW = 13.2N[19.1o] S. of W. 
maths
In a race over 4 km Ryan ran at a constant speed. Sophie, however, ran the first 2 km at a speed 1 km/h more than Ryan and ran the second 2 km at a speed 1 km/h less than Ryan. Who won the race? 
Mathematics
A single cell divides in two every 5 minutes and each new cell continues to divide every 5 minutes. How long does it take for the cell population to reach at least 1 million? 
Physics
Given: M1 = 10,000 kg, V1 = 10 m/s. M2 = 5,000 kg, V2 = ? V3 = 8 m/s = Velocity of M1 and M2 after colliding. Momentum before = Momentum after. M1*V1 + M2*V2 = M1*V3 + M2*V3. 10,000*10 + 5000*V2 = 10,000*8 + 5000*8, V2 = ? 
Momentum
Given: M1 = 0.5kg, Vi = 25 m/s. M2 = 2kg, V2 = 0. V3 = 5 m/s = Velocity of M1 and M2 after colliding. a. M1*V1 + M2*V2 = 0.5*25 + 2*0 = 12.5kgm/s = Momentum before colliding. b. M1*V3 + M2*V3 = Momentum after colliding. If a and b are equal, momentum is conserved. 
Physics
a. M*V1 = 3000 * 28. b. (M+500)*V2 = (3000+500) * 24 If a and b are equal, momentum is preserved. 
Physics
F = M*a. 20 = 32a, a = 0.625 m/s^2. V = Vo + a*t. 9 = 4 + 0.625t, t = ?. 
Math
First, we'll divide the 2nd pair of numbers by 5. Now we have: 3 and 1 3 and 5 7 and 9 Rule: Each pair of numbers has a difference of 2. 
Physics
L = V*T = V*(1/F) = Wavelength. 0.45 = 3.6 * 1/F, 1/F = 0.125, F = 8 Hz. 
math
1024803.8 = Area not covered. 
math
As = 32^2 = 1024 m^2. Ac = pi*r^2 = 3.14 * 16^2 = 803.8 m^2. AsAc = 1024  80j.8 = Area not reached. 
Trigonometry
You are welcome. 
Trigonometry
CosA = X/r = 6/10 = 0.6. A = 53.1o. 
Math
32 Ozs. = 2 Lbs. (5/2) * 4 = 10 Teaspoons. 
Mathematics
If 2^x = t, express the following in terms of t: a. 2^2x+1 b. 2^1x 
Algebra
Yes! Thanks! 
Algebra
Correction:Eq2: (V10)(T+2) = 315. V*T = (V10)(T+2). VT = VT+2V10T20, 2V+10T = 20, V  5T = 10, V = 5T + 10. In Eq1, replace V with 5T+10: (5T+10)T = 315, 5T^2 + 10T  315 = 0, T^2 + 2T  63 = 0, (T7)(T+9) = 0, T = 7, 9. T = 7h. V*T = 315. V*7 = 315, V = 45 mi/h. =10 t 
Algebra
Usual speed = V mi/h. Actual speed = (V10) mi/h. Eq1: V*T = 315. (V10)(T2) = 315. Since both Equations are = 315, they are also equal to each other: V*T = (V10)(T2). V*T = VT2V10T+20, 2V + 10T = 20, V + 5T = 10, V = 5T + 10. In Eq1, replace V with 5T+10. (5T+10)T = ... 
math
post it. 
math
Mixed numbers are, normally, changed to fractions before adding or subtracting: 10 1/2 + 6 1/4 = 21/2 + 25/4 = 42/4 + 25/4 = 67/4 = 16 3/4. Note: The fractions were placed over a common denominator. 
Math
#1 = X Deg. #2 = x+30o. x + (x+30) = 90. 
maths
5x2y = 6. m = A/B = 5/2 = 5/2 = Slope. (4,2) Y = mx + b. 2 = (5/2)4 + b, b = 12. Eq.: Y = (5/2)x  12. 
physical scienceasap
F*d = 10 Joules. 10*d = 10, 
Pre Algebra
Ac = 360  (218/245)360 = 39.7o = Central Angle. 
Physics
Fr = 5[0o] + 7[30o]. X = 5 + 7*Cos30 = 11.1 N. Y = 7*sin30 = 3.5 N. Fr = X + Yi = 11.1 + 3.5i = 11.6N.[17.5o]. = Resultant force. 
Physics
Given: M1 = 1.5kg, V1 = 2 m/s[90o]. M2 = 1.5kg, V2 = 10 m/s[0o]. V3 = Velocity of M1 and M2 after collision. Momentum before = Momentum after. M1*V1 + M2*V2 = M1*V3 + M2*V3. 1.5*2i + 1.5*10 = 1.5V3 + 1.5V3, 15 + 3i = 3V3, V3 = 5 + 1i = 5.1m/s[11.3o]. 
Math
P = 2*W + 2*L = 2(75/4) + 2(27/2) = 64.5 Yds. 
Physics
Circumference = 2pi*r = 6.28 * 0.35 = 2.2 m. Disp. = 2600m * 6.28rad/2.2m = 7422 rad. Circumference = 6.28 * 0.6 = 3.77 m. Disp. = 2600m * 6.28rad/3.77m = 4331 rad. 
math
A number line is a hor. line: P(2,0), M(x,0), B(12,0). x(2) = (12(2))/2. x+2 = (12+2)/2. X = ? 9 2,0) 
Physics
Length = 250cm/0.4N * 2.8N = cm. 
physics
We have to overcome static friction to get the motion started. We have to overcome kinetic friction to keep it going. We use kinetic friction because our system is already in motion. M*g = 90 * 9.8 = 882 N. = Wt. of stuntman = Normal force, Fn. Fk = u*Fn = 0.66 * 882 = 582 N... 
Physics
V = Vo + a*t. 0.56 = 0 + a*0.05, a = ? d = 0.5a*t^2. 
Physics
72km/h = 72000m/3600s = m/s. 
Math
Marisa has $X. Necklace: 3/4*x = $3x/4. Bal. = X3x/4 = x/4 Dollars. Earrings:1/2 * x/4 = x/8. Bal. = x/4x/8 = x/8. x/8 + (x/8+30) + x/8 = X. 3x/8  X = 30, 5x/8 = 30, X = 48. Necklace cost = 3x/4 = 3*48/4 = Earrings cost x/8 = 48/8 = bal. =