# Posts by Henry

Total # Posts: 13,577

Math
Db + Dc = 510 mi. Vb*t + Vc*t = 510. Vb*t + (Vb+33.4)t = 510. t = 8.5 hrs. Vb = ? Vc = Vb + 33.4.

algebra
V = y(5y^2+31y+6). A*C = 5*6 = 30 = 1*30. V = y(5y^2+(y+30y)+6) = 0. y(5y^2+y)(30y+6) = 0. y*y(5y+1)6(5y+1) = 0 6y^2(5y+1)(5y+1) = 0. 6y^2 = 0, Y = 0. 5y+1 = 0, Y = -1/5.

physics
Mg*h = 0.5M*V^2. h = 0.5V^2/g = 0.5*8.5^2/9.8 = 3.69 m. V^2 = Vo^2 + 2g*h. Vo = 1.5 m/s. g = 9.8 m/s^2. V = ?

Physics
F2*d2 = F1*d1. F2*6 = 4*3 = 12. F2 = 2 N.

math
X1 = ? X2 = 200. h = X1*Tan45 = (X1+200)*Tan30.

algebra
Width = X Ft. Length = (2x-4) Ft. Square: Each side = x + (2x-4). 2x+2(2x-4) + 4(x + 2x-4) = 264 Ft. 2x+4x-8 + 4x+8x-16 = 264. 18x - 24 = 264. 18x = 288. X = 16 Ft. Rectangle = 2*16 + 2(2*16-4) = 88 Ft. Square = 4(16+32-4) = 176 Ft. So the shorter piece of wire = 88 Ft.

a. P = Po*r*t/(1-(1+r)^-t). r = 6%. Po = 0.8 * 193,000 = \$154,400 = Amount financed. r = (6%/12)/100% = 0.005 = Monthly % rate expressed as a decimal. t = 30yrs * 12mo/yr. = 360 Months. P = 154,400*0.005*360/(1-1.005^-360) = \$333,254.16. Int. = P-Po = 333,254.16-154,400 = \$178...

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

math
M(-4,4), P(x,y), N(6,-2). x - (-4) = 3/4(6 - (-4). x + 4 = 3/4(6+4). X + 4 = 30/4 = 7 1/2. X = 7/2 = 3 1/2 = 3.5 y-4 = 3/4(-2-4). y-4 = -18/4 = -4 1/2. Y = -1/2 = -0.5 P(3.5,-0.5).

physics
h = Vo*t + 0.5g*t^2 = 80 m. -5*t + 4.9*t^2 = 80. 4.9t^2 - 5t - 80 = 0. Use Quadratic Formula: t = 4.58 s.

physics
k = 251N./0.488m = 514 N/m.

physics
a = F/M = 19.6/2.25 = 8.71 m/s^2. V^2 = Vo^2 + 2a*d. Vo = 0. V = ?

Algebra
I don't see the inequality sign.

Physics
h = 15.2*sin22 = 5.69 m. V^2=Vo^2 + 2g*h = 0 + 19.6*5.69 = 111.6 V = 10.6 m/s.

algebra

Physics
X = 1.5 m/s = Velocity of water. Y = 2.2 m/s = Velocity of the swimmer. Tan A = Y/X = 2.2/1.5 = 1.46667. A = 55.7o N. of E. Direction = 55.7o N. of W. = 34.3o W. of N.

Math
Sale Price = 0.96 * 850 = \$816. Cost = 0.80 * 816 = \$652.80

math
Your number is 32. 32 = 1*32. 32 = 2*2*2*2*2. Sum of its' digits = 3+2 = 5.

geometry
2268Ft^3 * 7.5gal./Ft^3 = 17,010 Gallons T = 17,010gal * 1min/11gal. = 1546 Min. = 27.8 Hours.

physics
KE = PE = M*g*h = 5*9.8*10 =

math
A. Correct. B. Cos15 = 22.5/L1. L1 = 22.5/Cos15 = 23.3. Length = L1 + L2 = 23.3 + 23.3 = 46.6

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.

science
M*V = 10 * 15 = 150.

physics
Incomplete.

1Physics
a. k=F/(L2-L1)=2*9.8/(15-10) = 3.92N/cm = 392N/m. b. F = 3.92N/cm * (20-10)cm = 39.2 N. a = F/M = 39.2/2 = 19.6 m/s^2. c. V^2 = Vo^2 + 2a*d = 0 + 2*19.6*0.10 = 3.92. V = 1.98 m/s. d.

electron theory and ohm law
I = E/R.

PHYSICS
F = M*a, M1 = F/a = 72/5 = 14.4 kg. M2 = 5/20 * M1 = 5/20 * 14.4 kg = 3.6 kg a = F/(M1+M2) = 72/(14.4+3.6) =

physics
Change in V. = 110km/h[S25oE] - 110km/h[S25oW]. X = 110*Cos25 - (-110*Cos25) = 199.4 m/s. Y = -110*sin25 - (-110*sin25) = 0. Change in V. = X = 199.4 m/s. The above angles are referenced to the y-axis. If the angles were referenced to the x-axis: X = 93 m/s, Y = 0. The angles ...

physics
0.4Vo = Vo + g*t. 0.4Vo = Vo + (-9.8*3). 0.6Vo = 29.4. Vo = 49 m/s. Vf^2 = Vo^2 + 2g*h. Vf = 0. g = -9.8 m/s^2. h = ?

Physics
Vf^2 = Vo^2 + 2g*h. h = ?

Math
X adult tickets: \$3.50 ea. Y child tickets: \$1.25 ea. Eq1: x + y = 37. Eq2: 3.5x + 1.25y = \$73.25. Multiply Eq1 by -3.5 and add the Eqs.

Physics
d = Vo*t + 0.5*a*t^2 = 1000 m. Vo*34.3 + 0.5*0.0377*34.3^2 = 1000 m. 34.3Vo + 22.2 = 1000 34.3Vo = 978. Vo = 28.5 m/s.

physics
Tan A = Y/X = 0.165/(31/2) = 0.01065. A = 0.61 Degrees = B = Angle the wire makes with the hor. -T2*Cos 0.61 + T1*Cos 0.61 = 0. T1*Cos 0.61 = T2*Cos 0.61. T1 = T2. T2*sin 0.61 + T1*sin 0.61 = M*g. Replace T2 with T1: T1*sin 0.61 + T1*sin 0.61 = 1.54*9.8 2*T1*sin 0.61 = 15.1 N...

Physics
See previous post: Mon, 11-23-15, 1:20 PM.

Physics
3a. Momentum conserved. b. Ma*Va + Mb*Vb = Ma*V + Mb*V. 0.50*0.40 + 0.750*0 = 0.50V + 0.75*V. V = ? c. Before: KE = 0.5Ma*Va^2. After: KE = 0.5(Ma+Mb)*V^2. KE will be less after the collision.

Algebra
1a. Fr = 3 - 0.5L/20km * d. Fr = 3 - 0.025d. Fr = Fuel remaining in liters. d = Distance traveled in km. b. Fr = 3 - 0.025*55 = 1.625 Liters. c. No. When d equals 130 km, Fr is negative which means the tank empties before 130 km is reached. The max distance can be calculated ...

College physics
In an inelastic collision, the bodies stick together. Therefore, their velocities are equal. M1*V1 + M2*V2 = M1*V + M2*V. 2500*15[90o] + 1600*16[225o]=2500V + 1600V. 37,500[90o] + 25,600[225o] = 4100V. 37,500i - 18,102 - 18,102i = 4100V. -18,102 + 19,398i = 4100V. 28443[-47o...

Science
Mass = 15Lb * 0.454kg/Lb = 6.81 kg. d = 2Ft * 1m/3.3Ft = 0.606 m. Work=F*d = Mg * d = 6.81*9.8 * 0.606 m = 40.4 J.

Physics
k = 100N./0.150m = 667 N/m.

Maths
Vo = 20m/s[30o]. Xo = 20*Cos30 = 17.3 m/s. Yo = 20*sin30 = 10 m/s. Yf = Yo + g*Tr. Yf = 0. g = -9.8 m/s^2. Tr = Rise time = ?. h = 15 + Yo*Tr + 0.5g*Tr^2 = Meters above sea level. g = -9.8 m/s^2. h = 0.5g*Tf^2. g = 9.8 m/s^2. Tf = Fall time = ?. Tr + Tf = Time in air. Dx = Xo...

science
1750 - 500 = 1250g = Wt. of oil. Density = 1250g/0.5L = 2500g/L.

math
1. C = 7p + 1.50. 2. C = 7*4 + 1.50 = 3. C = 7p + 1.50. C = 43.50. p = ?

physics
P = 0.2/0.8 * 100W. = 25 W.

Physics
1. Vf^2 = Vo^2 + 2g*h. Vf = 0. Vo = 12 m/s. g = -9.8 m/s^2. h = 2. V = 90,000m/3600s = 25 m/s. Vo = 126,000m/3600s = 35 m/s. V = Vo + a*t. a = (V-Vo)/t = (25-35)/t = -10/t. V^2 = Vo^2 + 2a*d. 25^2 = 35^2 + 2(-10/t)*800. 625 = 1225 + (-16,000)/t. -600 = -16000/t. 600t = 16000. ...

physics
Fr = F[0o] + F[126o] = F + F*Cos126 + (F*sin126)i = F - 0.588F + 0.809Fi=0.412F + 0.809i. Tan A = 0.809F/0.412F = 1.96359. A = 63o N. of E. = 63o CCW. Fr = 0.809F/sin63 = 0.908F[63o]

Physics AP
Wc = M*g = 32 * 9.8 = 314. N. Fn = 314*Cos38 = 247 N. = Normal force.

Physics
V^2 = Vo^2 + 2a*d. V = 0. Vo = 7.90 m/s. a = u*g = 0.41 * (-9.8) = -4.02 m/s^2. d = ?

Physics
Ws = M*g = 15 * 9.8 = 147 N. = Wt. of suitcase. Fn = Ws-T*sin45 = 147 - T*sin45 = 147-0.707T = Normal force. Fk=u*Fn=0.36*(147-0.707T) = 52.9-0.255T. T*Cos45-Fk = M*a. 0.707T-(52.9-0.255T) = M*0. 0.707T-52.9+0.255T = 0. 0.961T = 52.9 T = 55 N. Fn = 147 - 0.707*55 = 108 N.

Physics
a. See previous post: Thu, 11-19-15, 9:46 PM. b. V^2 = Vo^2 + 2g*h. Vo = 0. g = 9.8 m/s^2.

Physics
Mass = 180Lb * 0.454kg/Lb = 81.72 kg. h = 5mi * 1600m/mi 8000 m. h = 0.5g*t^2 = 8000. g = 9.8 m/s^2 t = ?

physics
E = 0.5*r + 0.5*6 Eq1: E = 0.5r + 3. E = 0.3*r + 0.3*(6+8). Eq2: E = 0.3r + 4.2. E = 0.5r + 3 = 0.3r + 4.2. 0.5r +3 = 0.3r + 4.2. 0.2r = 1.2. r = 6 Ohms = Internal resistance. E=0.5r + 0.5*R = 0.5*6 + 0.5*6 = 6 Volts

science
See Related Questions: Mon,11-5-12, 9:51PM.

Math
1. Work = F*d = 550 * 10*0.5 = Joules. 2. Power = Work/T = Joules/s.

Physics
D = 1200m[90o] + 200[0o] + 500[225o]. X = 1200*Cos90 + 200*Cos0 + 500*Cos225 = Y = 1200*sin90 + 200*sin0 + 500*sin225 = Tan A = Y/X, A = ?. D = X/Cos A, or Y/sin A.

physics
1. M*g = 7159 N. M = 7159/g = 7159/9.8 = 731 kg. Fp = 7159*sin25.6 = 3093 N. = Force parallel to the plank. Fap-Fp = M*a. Fap - 3093 = M*0 = 0. Fap = 3093 N. = Force applied. Work = Fap*d = 3093 * 2.26 = 6991 J. 2. Work = KE2-KE1 = 0.5M*V^2- 0 = 0.5*0.02*354^2 = 1253 J.

math
d = 2.78 - (-2.78) = 2.78 + 2.78 = 5.56.

Algebra
X = Larger number. Y = Smaller number. Eq1: X-Y = 86. x = y+86. 7y = x + 4. Eq2: x - 7y = -4. In Eq2, replace X with y+86: y+86 - 7y = -4. -6y = -90. Y = 15. x-15 = 86. X = 101.

Physics
Magnitude=3.6+3.4i + 5.5+1.9i + 2.5+3.4i = (3.6+5.5+2.5) + (3.4i+1.9i+3.4i) = 11.6 + 8.7i=Sqrt(11.6^2 + 8.7^2) = 14.5

Physics
F = 42N[83o] + 70N[300o]. X = 42*Cos83 + 70*Cos300 = Y = 42*sin83 + 70*sin300 = Tan A = Y/X, A = ? F = X/Cos A, or F = Y/sin A.

Math
1. 2*10^6. 2. 7*10^-7.

science
KE2-KE1 = 0.5M*V2^2 - 0.5M*V1^2 = 0.5*450*30^2 - 0.5*450*26^2 = 202,500 - 152,100 = 50,400 J.

Match
1. 27 3/5 + 15.9 = 27.6 + 15.9 = 43.5. 0.37 * 43.5 = 16.095 2. 27 3/5 + 15.9 = 27 3/5 + 15 9/10 = 27+6/10 + 15+9/10 = 42 + 15/10 = 42+1.5 = 43.5. 0.37 * 43.5 = 16.095 The first method is shorter and easier; I didn't have to deal with fractions.

Math
2000 mL = 2Liters. 2Liters * 3.5g/Liter = 7.0 Grams.

algebra
-1.7-(-13.4) = -1.7 + 13.4 = 11.7o

Physics
D=20[30o] + 30[90o] + 40[180o]+20[315o] X=20*Cos30+30*Cos90+40*Cos180+20*Cos315 = Y=20*sin30+30*sin90+40*sin180+20*sin315 = Tan A = Y/X. A = ?. D = X/Cos A, or Y/sin A.

Math
1. 18balloon * 2.5Ft/balloon. = 45 Ft. 45Ft. * 1yd/3Ft = 15 Yds.

Math
1. Add X striped balls. Add 10x/6 = 5x/3 white balls. x + 5x/3 = 112. 3x + 5x = 336. X = ? 5x/3 = ? 2. 4/6 = 14/16. 4*16 = 64. 6*14 = 84. The cross products are not equal; therefore, the ratios are not equivalent.

Math
C = 4.5*4 - 7 = \$11.

Math
T=30,000phones * 4h/1300phones=92.3 h. 1. A = X Degrees, B = (X-34) Degrees. Supplementary angles are angles whose sum is 180o: x + (x-34) = 180. X = ?. X-34 = ? 2. A = X Degrees, B = (2x+9) Degrees. x + (2x+9) = 90o. X = ? 2x+9 = ?

Physics
V^2 = Vo^2 + 2g*h = 0 + 19.6*1.54 = 30.2 V = 5.49 m/s.

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.

none
a = 16. b = 16. c = ? c^2 = a^2 + b^2.

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.

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.

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

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

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.

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

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

Algebra 1
W = 30 cm. L/4 + 12 = 30. L/4 = 18 L = 72 cm. h = 20 cm. V = L*W*h.

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.

Physics
V = 820*sin25 =

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

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

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

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.

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.

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

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.

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.

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

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.

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.

physics
Do you know the angle?

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

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 =

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

physics