# Posts by Henry

Total # Posts: 13,498

**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 ...

**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...

**Calculus**

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

**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.)

**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...

**Physics**

F = 0.119m * 110N./m =

**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 = ?.

**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.

**SCIENCE\PHYSICS**

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

**PHYSICS**

d = 5 + 5 = 10 m.

**PHYSICS**

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

**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...

**physics**

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

**Calculus**

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

**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-...

**maths**

P = Po(1+r)^n. r = (6%/2)/100% = 0.03 = Semi-annual % rate expressed as a decimal. n = 2comp./yr. * 1yr. = 2 Compounding periods. P = Po(1+0.03)^2 = Po*1.03^2 = 1.0609Po. I = P-Po = 1.0609Po-Po = 0.0609Po. I/Po * 100% = 0.0609Po/Po = 6.09% = Effective APR.

**Physic**

V = Vo^2 + 2g*h. Vo = 0, h = 20 m, V = ?

**physicsn**

Notes: 1. Fp = Force parallel with the hill. 2. Fn = Normal force. 3. Fk = Force of kinetic friction. 4. Ws = Wt. of skier.

**physicsn**

Ws = M*g = 9.8M. Fp = 9.8M*sin30 = 4.9M. Fn = 9.8M*Cos30 = 8.49M. Fk = u*Fn = u*8.49M. Fp-Fk = M*a. 4.9M-u8.49M = M*(-1.4) Divide by M: 4.9-8.49u = -1.4 -8.49u = -1.4-4.9 = -6.3 u = 0.74.

**Physics**

a. a=(Vf-Vo)/t = (5-0)/20 = 0.25 m/s^2. d1 = Vo*t + 0.5a*t^2 = 0 + 0.5*0.25*20^2 = 50 m.

**math**

a scooter is priced between $1000 and $2000. its price is a multiple of 10. All the digits in the price, except for the thousands digit, are even numbers. The value of the hundreds digit is 30 times the value of the tens digit. what is the price of the scooter?

**science**

Wb = M*g = 10 * 9.8 = 98 N. Fn = 98-40*sin30 = Normal force. Fk = u*Fn = Force of kinetic friction. a = (Fap*Cos30-Fk)/M.

**Physics**

a = F/m = 5/0.3 = 16.7 m/s^2. V = Vo + a*t. Vo = 20 m/s. t = 0.03 s. V = ?

**Physics**

Correction: Yf = 36.6 m/s.

**Physics**

h = 0.5g*t^2 = 68.2 m. 4.9t^2 = 68.2 t^2 = 13.92. t = 3.73 s. Dx = Xo*t = 4.2m/s * 3.73s. = 15.7 m. Yf^2 = Yo^2 + 2g*h. Yf^2 = 0 + 19.6*68.2 = 1336.72. Yf = 36.6 m. Vf = sqrt(Xo^2 + Yf^2) = Final velocity.

**math 1350**

Bob: X baseball cards. Ted: 2x " " Reggie: 2x-5 " " 2x-5 + x = 82. X = ?. 2x = ?

**science**

h = 0.5g*t^2.

**science**

d = 0.5*g*t^2.

**science/physics**

F = 9C/5 + 32.

**Physics**

Wc = M*g = 1300 * 9.8 = 12,740 N. = Normal force, Fn. Fp = Mg*sin A = Mg*sin 0 = 0. = Force parallel to the plane. Fk = u*Fn = 0.8 * 12,740 = 10,192 N. a = (Fp-Fk)/m = (0-10,192)/1300 = -7.84 m/s^2. d = (Vf^2-Vo^2)/2a = (0-(28^2))/-15.68 = 50 m.

**Physics - Check Answers ASAP**

1. M = 70 kg. Slope = 35o? L = 60 m. h = 60*sin35 = 34.4 m. Work = F*h = Mg*h = 70*9.8 * 34.4 = 23,608 J. 3. 19kW = 19kJ/s. = 19,000 J/s 6.8*10^7J * 1s./ 1.9*10^4J = 3580 s. = 0.994 h. or 1 h. 4. d = 0.5g*t^2 5. 24h/day * 365days/yr. * 3600s./h = 6. 200km[60o] N. of E. Dx = ...

**Urgent physics help**

A. D = 230mi/h * 2.5h = 575 mi. B. Dx = 575*Cos60 = C. Dy = 575*sin60 = D. Vr = 575mi[60o]/2.5h = Resultant velocity. Vx = Vr*Cos60 =

**Quick Physics check**

How did you arrive at your answer? See previous post: Wed, 10-21-15, 5:38 PM.

**physics**

Effective Intensity = 0.12 * 250W/m^2 = 30W/m^2. Area=(1200W * 1m^2/30W) = 40 m^2.

**physics**

Ws = M*g = 18 * 9.8 = 176.4 N. Fn = 176.4 - 45*sin30 = Normal force. Fk = u*Fn = Force of kinetic friction. F(net) = 45*Cos30-Fk

**physics**

See previous post: Fri, 10-23-15, 10:39 PM.

**physics**

Ws = M*g = 18 * 9.8 = 176.4 N. a. Fn = 176.4 - 45*sin30 = 153.9 N. = Normal force = Force perpendicular to the plane.

**Physics**

a = Fap/M = -250/50,000 = -0.005 m/s^2. Vf = Vo + a*t = 0. t = -Vo/a = 0.30/-0.005 = 60 s.

**Physics**

a. Wo = M*g = 4 * 9.8 = 39.2 N. d = 39.2N. * 1m/150N. = 0.261 m.

**MAth**

2^4 = 16. 2^-4 = 1/2^4 = 1/2^2*2^2 = 1/4*4 = 1/16.

**Physics**

h = 9.4*sin8.0 = 1.31 m. h = 0.5g*t^2 = 1.31 m. g = 9.8 m/s^2. t = ?

**Physics**

Vf = Vo + a*t = 20 + 2*4 = 28 m/s. Dc = 20*4 + 0.5*2*4^2 = 96 m. in 4 sec. Dc = 28m/s * 6s = 168 m. in 6 sec. Dc = 96 + 168 = 264 m. in 10 sec. Dt = 18m/s * 10s. = 180 m. in 10 sec. (264-8) - 180 = Distance in front of the truck.

**physics**

d = 2.06*sin28.8 = 0.992km, Due North.

**Science**

Vf = 100,000m/3600s. = 27.8 m/s. a = (Vf-Vo)/t = (27.8-0)/10 = 2.78 m/s^2

**Algebra**

Sun: X tickets were sold. Sat: 3x " " " Fri: 2x " " " $2(x + 3x + 2x) = $2160. X = ?

**math**

Assume 5 cm is measured on the drawing. d = 5cm * 3m/1cm = 15 m. = Actual distance.

**math**

(2/3)/6 = 2/3 * 1/6 = 2/18 = 1/9 cup.

**physics**

M*g = 1000 * 9.8 = 9800 N. Fp = 9800*sin33 = 5337 N. = Force parallel to the incline. a = Fp/M = 5337/1000 = 5.34 m/s^2.

**sri krishna**

3-4-5 triangle with each side multiplied by 4: hyp. = 20 = 5*4. 3*4 = 12. 4*4 = 16. So X = 4. so

**Math**

3/4 * M = 48. M = 4/3 * 48 = $64.

**Physics**

a. Vf = Vo + g*Tr = 0. Tr = -Vo/g = -15/-9.8 = 1.53 s. = Rise time. b. h1 = Vo*Tr + 0.5g*Tr^2 = Ht. above the roof. g = -9.8 m/s^2. h = h1 + 20. c. h = 0.5g*Tf^2. h = h1 + 20. g = 9.8 m/s^2. Tf = Fall time. Tf = ? Tr + Tf = Total flight time. d. Vf^2 = Vo^2 + 2g*h. Vo = 0. g...

**Physics**

Need more INFO.

**math**

d = 5days * 2(13/2)mi/day = 65 Miles. 65mi/4gal. = 16.25 mi/gal.

**math**

144/32 = 4 R16 = 4 Thirty-two inch pieces with 16 inches left.

**math**

(3 2/3)/2/3 = (11/3)/2/3 = 11/3 * 3/2 = 33/6 = 5 3/6 = 5 1/2 or 5 pieces.

**physics**

Yf^2 = Yo + 2g*h = 0. Yo = -2g*h = -2*(-9.8)*0.449 = 8.8 m/s. Yo = Vo*sin3.40 = 8.8 m/s. Vo = 8.8/sin3.4 = 148 m/s.

**math**

Sole X necklaces. Sold 3x watches. 4*x + 7*3x = $300. X = ?.

**Physics- PLEASE HELP!!**

Hannah and Tammy please show how you arrive at your answer.

**maths**

1 - (2/5 + 1/3) = 15/15 -(6/15 + 5/15)= 15/15 - 11/15 = 4/15 Left.

**physics**

D = 26km[90o] + 62km[60o]. X = 62*Cos60 = 31km. Y = 26 + 62*sin60 = 79.7 km. Q1. Tan A = Y/X = 79.7/31 = 2.57076. A = 68.7o = Direction. D = Y/sin A = 79.7/sin68.7 = 85.5 km[68.7o].

**Quick physics check**

Fr = 60[135o]CCW + 5[330o]CCW. X = 60*Cos135 + 5*Cos330 = -38.1 N. Y = 60*sin135 + 5*sin330 = 39.9 N. Q2. Tan A = Y/X = 39.9/-38.1 = -1.04794. A = -46.3o = 46.3o N. of W. = Direction. Fr=Sqrt(X^2 + Y^2)=Sqrt(38.1^2 + 39.9^2) = 55.2 N. = Resultant force.

**Physics**

M*g = 9990 N., M = 9990/9.8 = 1019 kg. V = 64.87 mi/h * 1600m/mi * 1h/3600s. = 28.83 m/s. KE = 0.5M*V^2 = 0.5*1019*(28.83)^2 = 423,481 J. PE = Mg*h = KE. 9990*h = 423,481. h = ?

**physics 11**

X = -2.7 m/s. Y = 1.3 m/s. Q2. a. Tan A = Y/X = 1.3/-2.7 = -0.48148. A = -25.7 m/s = 25.7o N. of W. = 64.3o W. of N. = Direction. Vr = Sqrt(X^2 + Y^2) = Sqrt(2.7^2+1.3^2)= 3.0 m/s = Resultant velocity. Dr = Sqrt(20^2 + 41.5^2) = 46.1 m. = Resultant distance. Dr = Vr*T = 46.1 m...

**Physics**

1. Vf^2 = Vo^2 + 2a*d Vo = 0. Vf = ?. 2. d = 0.5a*t^2.

**College Physics**

Wc = M*g = 1670 * 9.8 = 16,366 N. N/m = 16,366N./6.5m.

**Physics**

See previous post: Tue, 10-20-15, 11:26 AM.

**Physics**

See previous post: Tue,10-20-15, 11.26 AM.

**Physics. Appreciate the help I can get.**

a = (F-Fk)/M = (720-320)/400 = 1.0 m/s^2 A. d = Vo*t + 0.5a*t^2. Vo = 5 m/s. t = 6 s. d = ?. B. Work = F*d. C. Power = Work/t in J/s = Watts.

**NFCS**

Change = a*t = 0.219m/s^2 * 11.2s. =

**Physics 101**

Increase = (39-10)C*9.8*10^-6/C * 250 m. = 0.071 m.

**math**

Kim has X decals. 2x/3 on 5 cars. Remaining = x - 2x/3 = 1x/3. 2/5 * 1x/3 = 2x/15 decals on 2 bikes. Remaining = 6. 2x/3 + 2x/15 + 6 = X. 10x + 2x + 90 = 15x. 15x-12x = 90. 3x = 90. X = 30 = Total decals. 2x/3 = 60/3 = 20 Decals on 5 cars. 20decals/5cars = 4 decals/car.

**AP physics**

Vf^2 = Vo^2 + 2a*d = 0. a = -(Vo^2)/2d = -(10^2)/50 = -2.0 m/s^2 F = M*a = 60 * (-2.0)=-120 N. Retarding force.

**Physics 101 help (dumb it down please)**

M1*V1 + M2*V2 = M1*V + M2*V. M1 = 12,000 kg, V1 = 22 m/s. M2 = 1200 kg, V2 = 16 m/s. V = ?.

**PHYSICS**

Vf = 50.4km/h = 50400m/3600s = 14 m/s. a = (Vf-Vo)/t = (. Vo = 0. d = 0.5a*t^2.

**Physics**

M*g = 1600 * 9.8 = 15,680 N. Fp = 15,680*sin20 = 5363 N. Fn = 15,680*Cos20 = 14,734 N. Fk = u*Fn = 0.09 * 14,734 = 1326 N. Fw-Fp-Fk = M*a = M*0 = 0. Fw = Fp+Fk = 5363 + 1326 = 6689 N. = Force of the winch. Power = Fw * V = 6689 * 1.21 = 8094 J/s. = 8094 Watts.

**algebra**

-5(3-Q) + 4 = 5Q - 11. -15+5Q + 4 = 5Q - 11. 5Q - 5Q = -11 + 15 - 4. 0 = 0. Infinite solutions.

**Physics**

h = 0.5g*t^2 = 1.70 m. g = 9.8 m/s^2. t = ?.

**phPhysical Science**

Disp. = -16 + 20 = 4 km. V = 4km/(5+6)hrs. = 0.364 km/hr., East.

**AP physics**

h = 30*sin12 = 6.24 m. Vf^2 = Vo^2 + 2g*h = 0 + 19.6*6.24 = 122.3. Vf = 11.1 m/s.

**physics**

Yf = Yo + g*t = 12 - 10*2.4 = -12 m/s. Vf = sqrt(9^2 + 12^2) = 15 m/s.

**Physics**

Distance = 10 + 15 = 25 m. X = -10 m. Y = -15 m. Q3. Tan A = Y/X = -15/-10 = 1.50. A = 56.3o S. of W. = 236.3o CCW. Displacement = -15/sin236.3 = 18 m[236.3o] CCW.

**math**

b. 36cookies/2hr. = 18 Cookies/hr. T = 120Cookies * 1hr/18Cookies = 6.67 hrs.

**Physics**

Wb = M*g = 10 * 9.8 = 98 N. = Normal force, Fn. Fs = Force of static friction. Fap-Fs = M*a. 8 - Fs = M*a = M*0 = 0. Fs = 8 N. Fs = u*Fn = 8 N. u = 8/Fn = 8/98 = 0.082.

**physics**

Wc = M*g = 1.3 * 9.8 = 12.74 N. Fp = 12.74*sin25 = 5.38 N. = Force parallel to the incline. a. Fap-Fp = M*a. Fap-5.38 = M*0 = 0. Fap = 5.38 N. = Force applied.

**Physics**

M*g = 2.9 * 9.8 = 28.4 N. = Wt. of the brick = Normal force, Fn. Fk = u*Fn = 0.33 * 28.4 = 9.38 n. = Force of kinetic friction. Fap-Fk = M*a. Fap-9.38 = M*0 = 0. Fap = 9.38 N.

**maths**

5 yrs. ago: Amreen was X yrs. old. Juhi was 3x yrs. old. 10 years later: Amreen is x+10 yrs. old. Juhi is 3x+10 yrs. old. (3x+10) = 2(x+10). 3x + 10 = 2x + 20. X = 10. Amreen = x+10 = 10 + 10 = 20 yrs. old. Juhi = 3x+10 = 3*10 + 10 = 40 yrs. 0ld.

**Science**

1. False. The forces are balanced. 2. Air resistance. 7. Size of an object.

**physics**

M*g = 82 * 9.8 = 803.6 N. = Wt. of crate. = Normal force, Fn. Fk = u*Fn = 0.3 * 803.6 = 241 N. = Force of kinetic friction. F-Fk = M*a. 314-241 = 82*a. 82a = 73. a = 0.890 m/s^2. Vf^2 = Vo^2 + 2a*d. Vo = 0. Vf = ?.

**PHYSICS**

See previous post: Fri, 10-16-15, 12:41 AM.

**physics**

a. h = 0.5g*Tf^2. h = 414.1 m. g = 9.8 m/s^2. Tf = ? = Fall Time. Dx = Xo*Tf. Dx = 95.3 m. Xo = ? = Initial hor. speed. b. Y = Yo + g*Tf. Yo = 0. Y = ? = Ver. component of total velocity. Speed = Sqrt(Xo^2 + Y^2).

**physics**

Fo = (340+Vo)/(340-Vs1)*Fs1. Fo = (340+0)/(340-20) * 500 = 531.25 Hz. = The freq. heard by the observer. Fo = (340+0)/(340-23) * 500 = 536.28 Hz. Fb = 536.28 - 531.25 = 5.028 Hz = Beat freq. Note: The Freq. of S1 and S2 are equal, but their velocities are different. Therefore...

**Physics**

Dx = Vo^2*sin(2A)/g. Vo = 11 m/s. A = 30o g = 9.8 m/s^2. Dx = ?

**Physics**

a. h = 0.5g*t^2. g = 9.8 m/s^2. h = 1.05 m. t = ? b. Dx = Xo*t. Xo = 1.90 m/s. t = Value calculated in part a.

**physics**

Dx = Vo^2*sin(2A)/g = 44. m. Vo^2*sin(68)/9.8 = 44. Vo^2*0.0946 = 44. Vo^2 = 465.1. Vo = 21.6 m/s. at 34o below the hor. Xo = Vo*Cos A = 21.6*Cos34 = 17.9 m/s. Dx = 17.9*T = 44. T = 2.46 s. = Time in air.

**physics**

Vo = 15 m/s. Yf^2 = Yo^2 + 2g*h. Yf = 0. g = -9.8 m/s^2. h = 2 m. Yo = ?. sin A = Yo/Vo. A = ?

**Physics**

Vo = 120m/s[25o]. Xo = 120*Cos25 = 108.8 m/s. Yo = 120*sin25 = 50.71 m/s. Yf = Yo + g*Tr = 0 at max h. Tr = -Yo/g = 50.71/-9.8 = 5.17 s. = Rise time. Tf = Tr = 5.17 s. = Fall time. a. T = Tr + Tf = Time of Flight. b. Range = Xo*T. c. h max = Yo*Tr + 0.5g*Tr^2. g = -9.8 m/s^2.

**physics**

Wb = M*g = 330 * 9.8 = 3234 N. Fp = 3234*sin A = Force parallel to the incline. Fn = 3234*Cos A = Force perpendicular to the incline. Fs=u*Fn = 0.25 * 3234*Cos A = 809*Cos A = Force of static friction. Fp-Fs = M*a. 3234*sin A-8o9*Cos A = M*0 = 0. 3234*sin A = 809*Cos A. Divide...

**Physis**

h = 0.5g*t^2.

**Algebra 2**

If you mean: (x-3)/x = 3/5. Multiply Eq by 5x: 5x-15 = 3x. 5x - 3x = 15. 2x = 15. X = 7.5.