# Posts by Henry

Total # Posts: 13,334

**Physics**

M*g = 40 * 9.8 = 392 N. = Wt. of child. Fp = 392*sin35 = 224.8 N. = Force parallel to the incline. V^2 = Vo^2 + 2a*d = 2.5^2. 0 + 2a*4 = 6.25, a = 0.781 m/s^2. Fp-Fk = M*a. Fk = Fp-M*a = 224.8-40*0.781 = 193.6 N.

*November 17, 2016*

**physics**

c. F = 24.5N/m * 0.05m = 1.23 N.

*November 17, 2016*

**physics**

M*g = 0.5 * 9.8 = 4.9 N. = Wt. of object. a. k = F/d = 4.9N./(0.45-0.25)m = 24.5 N/m. b. 24.5N./m * (0.50-0.25)m = 6.125 N. 6.125 - 4.9 = 1.23 N. addition wt.

*November 17, 2016*

**Algebra**

Eq1: 5x - 4y = 10. Eq2: 2x + 8y = 4. Multiply Eq1 by 2 and add the Eqs: 10x - 8y = 20. +2x + 8y = 4. Sum: 12x = 24,m X = 2. In Eq2, replace x with 2: 2*2 + 8y = 4. Y = 0. M1 = -A/B = -5/-4 = 1.25. M2 = -2/8 = -0.25.

*November 16, 2016*

**science**

Incomplete.

*November 16, 2016*

**science**

V^2 = Vo^2 + 2g*h = 0 + 19.6*2 = 39.2, V = 6.26 m/s. PE = Mg*h = 0.98*1 = 0.98 J. KE = 0.5M*V^2 = 0.05*39.2 = 1.96 J.

*November 16, 2016*

**maths**

7/8-1/2 = 7/8-4/8 = 3/8 added. (3/8)/(7/8) = 3/8 * 8/7 = 24/56 = 3/7 of the bottle.

*November 16, 2016*

**Physics**

Dia. = 2 * 20 = 40 cm. hb = height below the surface. Dw = 1g/cm^3 = The density of water. hb = Dl/Dw * h = 40-8 = 32 cm. Dl/1 * 40 = 32, Dl = 0.8g/cm^3.

*November 16, 2016*

**math**

c = 10x + 1200 = 40x. X = 40 rides.

*November 15, 2016*

**math**

(2/7)/(3/4) * 1h = 2/7 * 4/3 * 1 =

*November 15, 2016*

**Math**

P = 0.85g + 0.07*0.85g = 0.91g.

*November 15, 2016*

**Mathe: NEEDHELP!**

6 oz./202.5mg * 52.5mg = 1.56 oz.

*November 15, 2016*

**math**

Correct.

*November 15, 2016*

**Math grade 6, Fractions**

Phillip had $X at 1st. X - 2x/5 = 5x/5-2x/5 = $3x/5 Left. = Jenny's amount. 3x/5 + 3x/5 = 360, 6x/5 = 360, X = $300.

*November 15, 2016*

**physics**

F1+F2+F3 = 0. F3 = -(F1+F2), F3 = -(8N[0o]+5N.[60o]), F3 = -((8+5*Cos60) + 5*sin60), F3 = -10.5 - 4.33i = 11.4N[20.9o] S. of W.

*November 15, 2016*

**PHYSICS**

k = 0.65N./0.053m = 12.3 N/m.

*November 14, 2016*

**math**

7*5 + 3 = 38 Oranges, initially. 38 - 5 = 33 Left.

*November 14, 2016*

**PHYSICS**

M*g = 3.5 * 9.8 = 34.3 N. = Wt. of block = Normal force(Fn). Fp = 15*Cos40 = 11.5 N. = Force parallel with the surface. 1. Fk = u*Fn = 0.25 * 34.3 = 8.58 N. 2. Fp-Fk = M*a. a = ?.

*November 14, 2016*

**math**

M = 0.454kg/Lb. * 80Lbs. = 36.3 kg. M*g = 36.3 * 9.8 = 356.0 N. Fp = 356*sin13.8 = 84.9 N. = Force parallel to the incline. F = Fp = 84.9 N.

*November 14, 2016*

**math**

Fr = 18.4[0o] + 13.1[16.5o]. X = 18.4 + 13.1*Cos16.5 = Y = 13.1*sin16.5 = Fr = Sqrt(x^2+Y^2).

*November 14, 2016*

**physics**

X = 1350-745 = 605 N. Y = 6300-3200 = 3100 N. Fn = Sqrt(X^2+Y^2) = Sqrt(605^2+3100^2) = 3158.5 N. Tan A = Y/X = 3100/605 = 5.12397. A = 79o N. of E. = Direction.

*November 13, 2016*

**Physics**

a. V = Vo + a*t. 1.6 = 0 + a*0.3, a = 5.33 m/s^2. F = M*a = 65 * 5.33 = 346.7 N.

*November 13, 2016*

**Math**

1760Ft/8.625 = 204 posts.

*November 13, 2016*

**English**

sample research paper about business

*November 13, 2016*

**Math**

a.Peaches = 0.2x. b. Apples = 0.25x. c. Lemons = 0.05x. d. Plums =

*November 12, 2016*

**Math**

X pieces of fruit. .2x + 0.25x + 0.05x + 0.1x + 0.2x + 0.15x = 0.95x. x - 0.95x = 0.05x = Remaining pieces. 0.05x = 8+4 = 12, X = 240 Pieces of fruit.

*November 12, 2016*

**Math**

I = Po*r*t = 275,000*0.03*1 = $8,250.

*November 12, 2016*

**Geometry**

(x+y)+7x+(3x-20)+(5y-10) = 360o. The opposite angles are equal: R = (x+y) = P = 7x. K = (5y-10) = A = (3x-20). (7x)+(7x)+(3x-20)+(3x-20) = 360, 20x = 400, X = 20. x+y = 7x = 7*20 = 140o.

*November 12, 2016*

**Physics**

PE = Mg*h = 98 J. 0.04*9.8*h = 98, h = 250 m. V^2 = Vo^2 + 19.6*h. V^2 = 0 + 19.6*250, V = ?. KE = 0.5M*V^2.

*November 11, 2016*

**Physics**

V = Vo + a*t = 130 rad/s. 30 + a*5 = 130, a = 20 rad/s^2. d = Vo*t + 0.5a*t^2. d = 30*5 + 10*5^2 = 400 rad.

*November 10, 2016*

**Pyhsics**

Correction: Y = 35*sin57 =

*November 10, 2016*

**Pyhsics**

35m/s[57o]. X = 35*Cos57 = Y = 35*sin7 =

*November 10, 2016*

**Physics**

a. M1*V1 + M2*V2 = M1*V + M2*V. 10*2 - 5*1 = 10V + 5V. V = ?. b. KE2 = 0.5M1*V^2 + 0.5M2*V^2. = KE after collision. c. KE1 = 0.5M1*V1^2 - 0.5M2*V2 = KE before collision.

*November 10, 2016*

**Math**

The number = N. sqrt(2N) = N/3. Square both sides: 2N = N^2/9, 18N = N^2, N^2 - 18N = 0, N(N-18) = 0, N = 0, and 18.

*November 10, 2016*

**Physics**

D = 30g/(60-50) = 30g/10cm^3 = 3g/cm^3.

*November 10, 2016*

**maths**

V2 = pi*r2^2 * h = 476,187 in^3. 3.14*(17.5)^2 * h = 476,187. h = ?.

*November 10, 2016*

**maths**

42barrels * 42gal/barrel = 1764 gal. 1764gal. * 1barrel/55gal. = 32 - 55 gal barrels. V1 = pi*r^2 * h = 3.14*(11.65)^2 * 34.9 = 14,881 in^3. = Vol. of a 55 gal. container. V2 = 32*V1 = 32 * 476,187 in^3 = Vol. of the 1764 gal container. Let r2 = 1.5r1 = 1.5 * 11.65 = 17.5 in. 8

*November 10, 2016*

**maths**

P = Po(1+r)^n. T = 7.5yr. * 12mo./yr. = 90 mo. P = 9230/mo. * 90mo. = $830,700. r = 0.0615. n = 1comp./yr. * 7.5yrs. = 7.5 compounding periods. Po = ?. I = P-Po.

*November 9, 2016*

**physics**

M*g = 1500 * 9.8 = 14,700 N. = Wt. of car. = Normal(Fn). V = Vo + a*t = 18. 0 + a*12 = 18, a = 1.5 m/s^2. d = 0.5a*t^2 = 0.75*12^2 = 108 m. Fr = 400 N. Fe-Fr = M*a. Fe = M*a+Fr = 2250 + 400 = 2650 N. = Force of engine. P = Fe*d/t = 2650 * 108/12 = 23,850 J/s = 23,850 Watts.

*November 9, 2016*

**Physics**

d = (30Lbs/12Lbs) * 3in. = 7.5 In.

*November 9, 2016*

**physics**

M1*g = 0.4 * 9.8 = 3.92 N. = Wt. of pkg.= Normal force(Fn). Fp = 3.92*sin 0 = 0 = Force parallel to the surface. Fap = M2*g = 0.2 * 9.8 = 1.96 N. = Force applied. Fs = us*Fn. = 3.92us. Fap-Fp-Fs = M*a. 1.96-0-3.92us = M*0 = 0, us = 0.50.

*November 9, 2016*

**Physics**

d = 15-10 = 5 cm = 0.05 m. F = 150N/m * 0.05m = 7.5 N. Work = F*d = 7.5 * 0.05 = 0.375 Joules.

*November 9, 2016*

**Physics**

a. t = 1s/1.6rad * 6.28rad/rev * 30rev = 117.75 s. b. V = Vo + a*t = 1.6 + 0.32*117.75 = 39.28 rad/s.

*November 8, 2016*

**physics**

M*g = 25*9.8 = 245 N. = Wt. of block. Fp = 245*sin32 = 129.8 N. = Force parallel to the incline. Fn = 245*Cos32 = 207.8 N. = Normal force. Fs = u*Fn = 0.45 * 207.8 = 93.5 N. = Force of static friction. F-Fp-Fs = M*a. a = 0. F = Ma+Fp+Fs = 0 + 129.8 + 93.5 = 223.3 N.

*November 8, 2016*

**Physics**

F*V = 40,000 W. F*50 = 40,000, F = 800 N.

*November 8, 2016*

**phisics**

Correction: After the brakes were applied, V = Vo + a*t = 0. 12 + a*5 = 0, a = -2.4 m/s^2. d3 = Vo*t + 0.5a*t^2. d3 = 12*5 - 1.2*5^2 = 30 m. d = d1+d2+d3 = 36 + 360 + 30 = 426 m. = Total distance covered.

*November 8, 2016*

**phisics**

a. V = a*t = 2 * 6 = 12 m/s. V = 0.012km/s * 3600s/h = 43.2 km/h. b. d1 = 0.5a*t^2 = 0.5*2*6^2 = 36 m. d2 = V*t = 12 * 30 = 360 m. V = Vo + a*t = 0. 12 + a*6 = 0, a = -2 m/s^2 d3 = Vo*t + 0.5a*t^2. d3 = 12*6 - 1*5^2 = 47 m. d = d1+d2+d3 = Total distance.

*November 8, 2016*

**Physics**

b. KEb = 0.5M1*V1^2 + 0.5M2*V2^2 = Kinetic energy before collision. KEa = 0.5M1*V^2 + 0.5M2*v^2 = Kinetic energy after collision. KE Lost = KEb - KEa. %KE Lost = KE Lost/KEb.

*November 6, 2016*

**Physics**

M1 = 1200kg. V1 = 30km/h = 30,000m/3600s = 8.33 m/s[0o]. M2 = 1500 g. V2[90o] = ?. a. M1*V1 + M2*V2 = M1*V + M2*V. 1200*8.33 + 1500V2[90o] = 1200V[64o] + 1500V[64o]. 10,000 + 1500V2[90o] = 2700V[64o]. The hor. components before the collision = Hor. components after collision: ...

*November 6, 2016*

**math**

See previous post: Sun, 11-6-16, 4:19 AM.

*November 6, 2016*

**math**

Tan70 = 34/d1, d1 = 34/Tan70 = 12.4 m. = Jane's distance from the tower. Tan50 = 34/d2, d2 = 34/Tan50 = 28.5 m. = Bill's distance from the tower. d1+d2 = 12.4 + 28.5 = 40.9 m. Apart.

*November 6, 2016*

**Maths**

Tan35 = h/d, h = d*Tan35. Tan16 = h/(d+950), h = (d+950)Tan16. d*Tan35 = (d+950)*Tan16. 0.7d = 0.287d + 272.4, 0.413d = 272.4, d = 659.6 m. h = d*Tan35 = 659.6 * Tan35 = 461.8 m.

*November 6, 2016*

**physics**

h = 0.5g*t^2 = 4.9*10^2 = 490 m.

*November 6, 2016*

**physics**

V^2 = Vo^2 + 2g*h = 0 + 19.6*7000, V = 370 m/s. V = 0.370km/s * 3600s/h = 1333 km/h.

*November 6, 2016*

**physics**

a. V = 3 + 5i = 5.83km/h[59o]. b. d = 3km/h * 0.5h = 1.5 km. c. Width = 5km/h * 0.5h = 2.5 km.

*November 6, 2016*

**math**

Vo = 82m/s[13o]. Yo = 82*sin13 = 18.45 m/s. h = Yo*t = 18.45m/s * 420s. = 7747 m.

*November 6, 2016*

**math**

Tan A = h/d. Tan 6 = 27,000/d, d = ?.

*November 6, 2016*

**Business mathematics**

P = Po(1+r)^n. Po = 7000 - 2000 = $5000. r = 0.05/12mo. = 0.00417/mo. n = 1Comp./mo. * 15mo. = 15 Compounding periods. P/15 = Monthly payment.

*November 6, 2016*

**Physics**

M*V1 + M*V2 = M*V3[45o] + M*V4[30o]. V1 + 0 = V3[45o] + V4[30o]. 44 = V3*Cos45 + V4*Cos30. Eq1: 0.707V3 + 0.866V4 = 44, V3 = 62.2-1.22V4. V3*sin45 + V4*sin30 = 0. Eq2: 0.707V3 + 0.5V4 = 0, 1.414V3 + V4 = 0, V4 = -1.414V3. V3 = 62.2 - 1.22*(-1.414V3), V3 = 62.2 + 1.73V3, V3 = -...

*November 5, 2016*

**Physics**

Northwest = 45o N. of W. = 135o CCW from +x-axis. Disp. = 18km[135o] - 9. Disp. = 18*Cos135-9 + 18*sin135 = -12.73-9 + 12.73i = -21.73 + 12.73i = 25.2km[-30.4o] = 25.2km[30.4o] N. of W.

*November 5, 2016*

**Physics**

See previous post: Wed, 11-2-16, 9:11 PM.

*November 4, 2016*

**Physics**

9/9 - 1/9 = 8/9 of its' volume below water. Dw = 1 g/cm^3. Vb = Di/Dw * Vi. 8/9 = Di/1 * 1, Di = 0.889 g/cm^3.

*November 4, 2016*

**PHYSICS (REALLY DIFFICULT PLEASE HELP)**

Fp = Force parallel to the surface.

*November 4, 2016*

**PHYSICS (REALLY DIFFICULT PLEASE HELP)**

Fp = Mg*sin 0 = 0. Fn = Mg*Cos 0 = Mg = Normal force. Fk = u*Fn = 0.50*Mg. Fp-Fk = M*a. 0-0.5Mg = M*a, Divide by Mg: -0.5 = a/g = a/-10, a = 5 m/s^2. V^2 = 60^2 - 10d. 0 = 3600 -10d, d = 360 m.

*November 4, 2016*

**Physics**

a. V1^2 = Vo^2 + 2g*h. V1^2 = 0 + 20*8, V1 = 12.65 m/s. V^2 = V2^2 + 2g*h. 0 = V2^2 - 20*2, V2 = 6.32 m/s. M*V1-M*V2 = 0.1*12.65 - 0.1*6.32 = 0.633 = Change in momentum. b. V = V2 + a*t. 0 = 6.32 - a*0.1, a = 63.2 m/s^2. F = M*a = 0.1 * 63.2 = 6.32 N.

*November 4, 2016*

**Physics**

a. M = 21 kg on earth and the planet. b. M*g = 21*9.8 = 205.8 N. = Wt. on earth. 21*12 = 252 N. = Wt. on the planet.

*November 4, 2016*

**Science**

1st stone: V = Vo + g*Tr. 0 = 20 - 10Tr, Tr = 2 s. = Rise time. 1. 2nd stone: V = Vo + g*t. 10 = 20 - 10t, t = 1 s. in motion. 2. 1st stone: V = Vo + g*t. = 0 + 10*1 = 10 m/s. When they meet.

*November 3, 2016*

**Biophysics**

Po = 0.15*Pi = 0.15 * 450 = 67.5 Watts.

*November 3, 2016*

**maths**

Consider the 4 points A(1,5), B(-4,6), C(0,0), D(-12,12). Find the gradients of the lines: (b) CD; (c) BD.

*November 3, 2016*

**physics -damon help**

1. The resistance of the inductor is assumed to be zero. P = Vr*I = 40 * 2 = 80 Watts. 2. pf = Cos A = Vr/E = 40/50 = 0.8.

*November 3, 2016*

**Physics**

See previous post: Wed, 11-2-16, 8:37 PM.

*November 3, 2016*

**Physics**

F2 = 2F1 = 2 * 192 = 384N.[25o] W. of N.

*November 2, 2016*

**Physics**

F1 + 2F1[115o] = 350i. F1 + 2F1*Cos115 + (2F1*sin115)i = 350i, F1 - 0.845F1 + (1.81F1)i = 350i, 0.155F1 + (1.81F1)i = 350i. F1(0.155+1.81i) = 350i, F1(1.82[85.1] = 350[90o], F1 = 192N.[4.9o]. F2 ====

*November 2, 2016*

**Physics Urgent!**

M*g = 60 * 9.8 = 588 N. Fp = 588*sin A. = Force parallel to the incline. Fn = 588*Cos A = Normal force. Fs = us*Fn = 0.55*(588*Cos A = 323.4*Cos A. Fp-Fs = M*a. 588*sin A-323.4*Cos A = 60*0 = 0, 588*sin A = 323.4*Cos A, Divide by 588: sin A = 0.55*Cos A, Divide by Cos A: sin A...

*November 2, 2016*

**Physics**

Fp = Force parallel to the incline. Fn = Normal force.

*November 2, 2016*

**Physics**

2. M*g = 1200*9.8 = 11,760 N. = Wt. of car. = Normal force(Fn). Fp = Mg*sin 0 = 0. Fk = uk*Fn = 0.1323*11,760 = 1556 N. Fp-Fk = M*a. 0-1556 = 1200a, a = -1.30 m/s^2. V^2 = Vo^2 + 2a*d. 0 = (20.1)^2 - 19.6d, d = ?.

*November 2, 2016*

**Physics**

Divide by Mg: 0.407-0.914u = a/g = 3.1/-9.81, 0.407-.914u = -0.316, uk = 0.791.

*November 2, 2016*

**Physics**

1. Fp = Mg*sin24 = 0.407Mg. Fn = Mg*Cos24 = 0.914Mg. Fk = u*0.914Mg. Fp-Fk = M*a. 0.407Mg-u*0.914Mg = M*a.

*November 2, 2016*

**physics**

V1 = Speed of 1st bus. V2 = 2V1 = Speed of 2nd bus. d1 + d2 = 240. V1*t + 2V1*t = 240, 3V1*t = 240, 3V1*1 = 240, V1 = 80 km/h. V2 = 2V1 = 2*80 = 160 km/h.

*November 2, 2016*

**physics**

1rev/12h * 1h/3600s. = 2.315*10^-5 rev/s.

*November 2, 2016*

**physics**

See previous post: Sat, 10-29-16, 2:04 PM.

*November 1, 2016*

**physics**

1rev/12h * 1h/3600s. = 0.00002315 = 2.315*10^-5 rev/s.

*November 1, 2016*

**physics**

See previous post: Sat, 10-29-16, 9:35 AM.

*November 1, 2016*

**Math**

Flavored.

*November 1, 2016*

**math**

Width = W meters. Length = 2W meters. W * 2W = 480 m^2. 2W^2 - 480 = 0, W^2 - 240 = W = 15.5 Meters. 2W = 2 * 15.5 = 31 Meters.

*November 1, 2016*

**Maths**

a. m = *y2-y1)/(x2-x1) = (6-5)/(-4-1) = -1/5. Use same procedure for part b, and c.

*November 1, 2016*

**Maths**

Consider the 4 points A(1,5), B(-4,6), C(0,0), D(-12,12). Find the gradients of the lines: (a) AB; (b) CD; (c) BD.

*November 1, 2016*

**Maths please help**

See previous post: Tue, 11-1-16, 11:33 AM.

*November 1, 2016*

**science**

d = r*t. 5+2 = 3*t, t = 2.33 s. r = d/t = 7m/2.33s. = 3 m/s. Disp. = 5-2 = 3 m. V = D/t = 3m/2.33s. = 1.29 m/s.

*November 1, 2016*

**maths**

(iii). x-1 = 3(-4-x). x-1 = -12-3x, X = -11/4. y-3 = 3(-1-y). y-3 = -3-3y, Y = 0.

*November 1, 2016*

**maths**

(1,3), (x,y), (-4,-1). (i). -4-x = 2(x-1). -4-x = 2x-2, X = -2/3. -1-y = 2(y-3). -1-y = 2y-6, Y = 5/3. (ii). x-1 = -4-x. X = -3/2. y-3 = -1-y. Y = 1.

*November 1, 2016*

**Physical**

Depth = Dwo/Dwa * h = (800/1000) * 0.5 = 0.40 m.

*November 1, 2016*

**Physics**

V = Vo + a*t. 0 = 32 - 1*t, t = 32 s.

*November 1, 2016*

**pre algebra 8th**

See previous post.

*October 31, 2016*

**pre algebra**

1. Your inequality is correct. 3200 + 0.02d >= 4000. 0.02d >= 4000-3200, 0.02d >= 800, d >= $40,000. 2. Correct.

*October 31, 2016*

**URGENT ANY PhYSIcs teacher help thouroighly pls**

M*g = 750 * 9.8 = 7350 N. = Wt. of car = Normal force(Fn). Fp = 7350*sin 0o = 0 = Force parallel to the plane. Fk = u*Fn = 0.5 * 7350 = 3675 N. = Force of kinetic friction. Fp-Fk = M*a. 0-3675 = 750a, a = -4.9 m/s^2. Or u = a/g. 0.5 = a/-9.8, a = -4.9 m/s^2.

*October 31, 2016*

**physics**

Incomplete.

*October 31, 2016*

**Physics**

Correction: 70-10 = 60 Addition seconds to stop.

*October 31, 2016*

**Physics**

Vo = 7.0rev/s. V = 60rev/10s = 6rev/s. V = Vo + a*t. 6 - 7 + a*10, a = -0.1 rev/s^2. V = Vo + a*t. 0 = 7 - 0.1*t, t = 70 s. = Stopping time. 70 - 6 = 64 additional seconds to stop.

*October 31, 2016*

**Math**

V = Vo + g*Tr. 0 = 64 - 32Tr, Tr = 2 s. = Rise time. h = -16Tr^2 + 64Tr + 192. h = -16*2^2 + 64*2 + 192 = 256 Ft. h = 0.5g*Tf^2. 256 = 16Tf^2, Tf = 4 s. = Fall time. Tr+Tf = 2 + 4 = 6 s. To hit gnd.

*October 30, 2016*