Wednesday

December 7, 2016
Total # Posts: 12,452

**maths**

Let adjacent angle = X degrees. There are 4 angles; the opposite angles are equal. x + (x-20) + x + (x-20) = 360o. X = 100o, (x-20) = 80o.

*June 14, 2016*

**Physics**

Vo = 120m/s[35o]. Xo = 120*Cos35 = 98.3 m/s. Yo = 120*sin35 = 68.8 m/s. a. Y = Yo + g*Tr = 0. 68.8 - 9.8Tr = 0, Tr = 7.02 s. = Rise time. h = ho + Yo*Tr + 0.5g*Tr^2 = 20 + 68.8*7.0 - 4.9*7.0^2 = 261.5 m. above gnd. 0.5g*Tf^2 = 261.5. 4.9*Tf^2 = 261.5, Tf = 7.31 s. = Fall time...

*June 12, 2016*

**Algebra**

If 1/2 = 2/4, Then 2/1 = 4/2.

*June 11, 2016*

**physics**

Correction: Speeder: Vo = 117,000m/3600s = 32.5 m/s. Ds = 32.5*t = Distance traveled by speeder. Patrol car: a = (7600m/3600s)/s = 2.11 m/s^2. a. 32.5t = 0.5*2.11*t^2, 1.05t = 32.5, t = 31 s. b. Ds = Dp = 32.5*t = 32.5*31 = 1006 m.

*June 10, 2016*

**physics**

Speeder: Vo = 117,000m/3600s = 32.5 m/s. Ds = Vo*t = 32.5*t. = Distance traveled by speeder. Patrol car: a = (7600m/3600s)/s = 2.11 m/s^2. V = 175,000m/3600s = 48.6 m/s. Vo = 0. V^2 = Vo^2 + 2a*D, Dp = V^2/2a = (48.6)^2/4.22 = 560 m = Distance traveled by patrol car. a. Ds = ...

*June 10, 2016*

**Pre-Calculus**

X type A printers. Y type B printers. Eq1: x + y => 100. Eq2: 45x + 35y => 3850. Multiply Eq1 by -35 and add the Eqs: -35x - 35y => -3500. +45x + 35y => +3850. 10x => 350, X => 35 Type A printers. In Eq1, replace x with 35: 35 + y => 100, Y => 65 Type B...

*June 8, 2016*

**maths,science, physics**

M1*V1 + M2*V2 = M1*V + M2*V. 4000*3.5 + M2*0 = 4000*2 + M2*2 14,000-8000 = 2M2 M2 = 3,000 kg.

*June 5, 2016*

**Physics**

V = Vo + g*Tr = 0. Tr = -Vo/g = -20/-9.8 = 2.04 s. = Rise time. h = ho + Vo*Tr + 0.5g*Tr^2. h = 29 + 20*2.04 - 4.9*2.04^2 = 49.4 m Above gnd. 0.5g*Tf^2 = 49.4, 4.9Tf^2 = 49.4, Tf^2 = 10.08, Tf = 3.18 s. = Fall time. T = Tr + Tf = 2.04 + 3.18 = 5.22 s. To strike the water.

*June 4, 2016*

**physics**

F = 8beats/8s. = 1beat/s = 1cycle/s = 1 Hz.

*June 4, 2016*

**Physics**

All angles are measured CCW from due east. D = 29km[60o] + 20km[270o] + 10km[150o] =

*June 3, 2016*

**Physics**

Correction: D = 23i + 19.9+11.5i = 19.9 + 34.5i = 39.8m[60.0o]. Direction = 60.0o N . of E.

*June 3, 2016*

**Physics**

D = 23[90o] + 23[30o]. D = 23i + 19.9+11.5i = 19.9 + 42.9i = 47.3m[65.1o]. Direction = 65.1o N. of E.

*June 3, 2016*

**Physics**

V = 36km/h = 36000m/3600s = 10 m/s. V = Vo + a*t = 10 m/s. 0 + a*10 = 10, a = 1 m/s^2. V = Vo + a*t = 0. 10 + a*20 = 0, 20a = -10, a = -0.5 m/s^2.

*May 31, 2016*

**physics**

Vb = Di/Dw * Vi = Vi/9. Di/1000 * Vi = Vi/9, Divide both sides by Vi: Di/1000 = 1/9, Di = 1000/9 = 111.11 kg/m^3 = Density of the ice cube.

*May 31, 2016*

**Physics**

k = 50N/(25-20)cm = 10N/cm. L = 20 + 100N*1cm/10N = 20 + 10 = 30 cm.

*May 28, 2016*

**finance**

a. Net Income = 591,000 - 255,000 - 0.36*591,000 = b. $591,000. c. 0.36 * 591000 =

*May 22, 2016*

**General Chemistry**

Thank you bobpursley..how can I determine the max concentration for Fe(OH)3 that will dissolve though?

*May 20, 2016*

**General Chemistry**

Ferric Hydroxide, Fe(OH)3, is an insoluble salt with a solubility of 10^-39. 1) What is the maximum concentration of ferric hydroxide that can dissolve? 2) Using Le Chatalier's Principle, explain why iron (III) solutions are more soluble in acidic solution.

*May 20, 2016*

**math**

Smaller box = 2*2*3. Larger box = 3*4*5. 2 small boxes stacked = L*W*2h = 2*2*6. Too tall to fit in large box. 2 small boxes side-by-side = L*2W*h = 2*4*3. So 2 smaller boxes will fit in the larger box.

*May 20, 2016*

**Physics**

K = 0.5N/0.0.6cm = 0.833 N/cm. Length = 35 + 2N*1cm/0.833N = 37.40 cm. Increasing the force above 2N do not increase length further.

*May 14, 2016*

**Science**

GPS or Geographic Positioning System

*May 10, 2016*

**math**

The first and the last terms of an Arithmetic Progression are 6 and 171 in that order. If there are 14 terms, find the 16th term of the Arithmetic Progression.

*May 8, 2016*

**Physics**

See previous post.

*May 7, 2016*

**Physics**

3.10km[25o]. 3.1*sin25 = 1.31 km due north, 3.1*Cos25 = 2.81 km due east. I assumed you meant 25o N. of E, because northeast = 45o.

*May 7, 2016*

**physics**

Convert to unit Vector: (51.2,30.8). Tan A = Y/X = 30.8/51.2 = 0.60062, A = 31o. R = = X/Cos A = 51.2/Cos31 = 59.7km[31o]. (x/59.7,y/59.7) = (51.2/59.7,30.8/59.7) = (0.86,0.52).

*May 7, 2016*

**physics**

a. 30km[315o,CCW] = 21.21 - 21.21i. b. 60km[60o,CCW] = 30 + 52i. R = 21.21-21.21i + 30+52i = 51.2 + 30.8i.

*May 7, 2016*

**physics**

Vo*t + 0.5a*t^2 = 62.4 m. Vo*4.2 - 0.5*5.6*4.2^2 = 62.4, 4.2Vo - 49.39 = 62.4, 4.2Vo = 111.79, Vo = 26.6 m/s. V^2 = Vo^2 + 2a*d. Vo = 26.6 m/s, a = -5.6 m/s^2, d = 62.4 m, V = ?.

*May 7, 2016*

**physics**

V = Vo + a*t. V = 0, a = -2.5 m/s^2, t = 10 s, Vo = ?.

*May 7, 2016*

**Math?**

The Lateral area is the area of the 4 vertical sides: A = 2(5*7) + 2(16*5) = 230 m^2.

*May 6, 2016*

**Maths**

2. V = Vo(1-r)^n. a. V = 1500(1-0.21)^6 = $364.63 b. V = 1500(1-0.21)^n = 60. 1500(0.79)^n = 60, 0.79^n = 60/1500 = 0.04, n*Log0.79 = Log0.04, n = Log0.04/Log0.79 = 13.7 Years.

*May 6, 2016*

**math**

Ar = Ab - Ad. Ar = 15000 - 15000*(0.075/360)*120 = $14,625 = Amt. received(proceeds). Ar = Amount received. Ab = Amount borrowed. Ad = Amount discounted.

*May 6, 2016*

**math 5th grade**

L = 5/6 yds. = 2 1/2 Ft. W = 3*2 1/2 = 15/2 = 7 1/2 Ft. Area = L*W = 2 1/2 * 7 1/2 = 5/2 * 15/2 = 75/4 = 18 3/4 square Ft. Or Area = L*W = 5/6 * 2 1/2 =[ 5/6 * 5/2 = 25/12 = 2 1/12 sq. yds. 1yd = 3ft, 1sq yd. = 3^2 = 9 sq. Ft. A = 2 1/12sq yds * 9sq ft/sq yd = 25/12 * 9 = 225/...

*May 5, 2016*

**physics**

Vo = 2 m/s[30o]. Xo = 2*Cos30 = 1.73 m/s. Yo = 2*sin30 = 1.0 m/s. Y = Yo + g*Tr. Y = 1 -9.8*Tr = 0, -9.8Tr = -1, Tr = 0.102 s. = Rise time or time to reach max ht. Tf = Tr = 0.102 s. = Fall time. Tr+Tf = 0.102 + 0.102 = 0.204 s. = Time in air. Y = 1 - 9.8*0.2 = -0.96 m/s. Y = ...

*May 5, 2016*

**physics**

Cos30 = V/10. V = ?.

*May 5, 2016*

**physics**

Correction: B. Impulse = F*t.

*May 5, 2016*

**physics**

a = (V-Vo)/t. V = 50 m/s, Vo = 0, a = ?. A. F = M*a. B. Impulse = M*t. C. Momentum ch. = M*V-M*Vo. C.

*May 5, 2016*

**Science (PhYsics)**

C = pi*2r = 3.14 * 1 = 3.14 m. Vo = 200rev/min * 3.14m/rev. * 1min/60s = 10.5 m/s. Since the velocity is constant, the acceleration is zero: a = (V-Vo)/t = (10.5-10.5)/t = 0/t = 0.

*May 5, 2016*

**Mathematics**

P1/P2 = 2/5, A1/A2 = (2/5)^2 = 4/25.

*May 5, 2016*

**physics**

b. Fk = u*Mg = 0.25 * 1.5*9.8 = 3.675 N. PE = KE - Fk*d = 19-3.675*d = 1.5*9.8*d, 19-3.675d = 14.7d, -18.375d = -19, d = 1.03 m.

*May 4, 2016*

**physics**

V = 75000m/h * 1h/3600s = 20.83 m/s. a. KE = 0.5M*V^2. b. PE = Mg*h = KE(Part "a"). g = 9.8 m/s^2, h = ?.

*May 4, 2016*

**Physics**

d = r*t =

*May 4, 2016*

**math**

Vb = 40km/2h = 20 km/h. Downstream. Vb = 40km/4h = 10 km/h. Upstream. Vb = (20+10)/2 = 15 km/h. In still water. Vs = 20 - 15 = 5 km/h. = Velocity of the stream.

*May 4, 2016*

**physics**

A. Work = F*d = 75 * 2 = 150 J. B. Work also = Change in kinetic energy = 0.5M*V^2 = 150, M = 65 kg, V = ?.

*May 4, 2016*

**physics**

A. k = 15N/0.450m = 33.3 N/m. B. F = 0.75m * 33.3N/m = 25 N.

*May 4, 2016*

**Physics**

D = 2.5 + 5i = 5.24 km[63.43o].

*May 4, 2016*

**HELP MATH ASAP**

Your problems are written in a very unconventional manner which makes them difficult to read and understand. Normal format: (x,y) = (3,4), (6,7).

*May 4, 2016*

**phy**

V = 45rev/min * 6.28rad/rev * 1min/60s = 4.71 rad/s. V = Vo + a*t = 4.71. 0 + a*4.5 = 4.71, a = 1.05 rad/s^2. D = Vo*t + 0.5a*t^2. D = 0 + 0.5*1.05*3^2 = 4.73 rad. V = Vo + a*t = 0 + 1.05*3 = 3.15 rad/s.

*May 4, 2016*

**Science**

E = 40 Volts, r = 5 Ohms, R = 15 Ohms. I = E//(r+R) = 40/20 = 2A. Vt = I*R = 2 * 15 = 30 Volts.

*May 2, 2016*

**science**

Q1. Matter. Q3. Density = 9g/45mL = 0.2 g/mL.

*May 2, 2016*

**science**

The answer is A.

*May 2, 2016*

**physics**

Cos30 = d/1780, d = ?.

*May 2, 2016*

**Math**

8W = 3F, 1W = 3/8F, 4W = 12/8F = 3/2F, 1D = 3/2F, 8D = 12F.

*May 1, 2016*

**Solid Mensuration**

There are 6 identical circles; the radius of each circle is 2 in.

*April 30, 2016*

**Solid Mensuration**

Diameter = 2/6 = 1/3 Ft. = 4 in. Radius = 1/2 * 4 = 2 In.

*April 30, 2016*

**Maths**

2^n = 50. n*Log2 = Log50, n = Log50/Log2 = 5.64 or 6 10-day periods to reach 50 times current populat5ion.

*April 29, 2016*

**7th grade math**

See previous post: Thu, 4-28-16, 8:26 PM.

*April 28, 2016*

**7th Grade Matj**

The number 25 should be 24. K = 27/24 = 9/8 = 1.125. Eq: Y = kx, or Y = 1.125x.

*April 28, 2016*

**math**

sin55 = Y/82, Y = 82*sin55 = 67.2 Ft., h = 67.2 + 3 = 70.2 Ft.

*April 28, 2016*

**science**

M*g = 2 * 9.8 = 19.6 N. d = 19.6N. * 1m/1500N. = 0.0130 m. = 1.30 cm.

*April 28, 2016*

**math**

a. Vb*t + Vc*t = 210. 60t + 80t = 210, t = ?. b. d = Vc*t.

*April 28, 2016*

**math**

A. V = 50mi/(45/60)h = 62.5 mph. d = V*t = 300. t = 300/62.5 = 4.8h. B. t = 4.8h - 48min. = 4.8h - 0.75h = 4.05h. d = V*t. d = 300 mi., t = 4.05h., V = ?.

*April 28, 2016*

**physics**

V^2 = Vo^2 + 2a*d. V = 45 m/s, a = -6.1 m/s^2, d = 59.7m+25m, Vo = ?. V = Vo + a*t. V = 45 m/s, Vo = previous calculation, a = -6.1 m/s^2, t = ?.

*April 28, 2016*

**Physics**

d = Vo*t, d = 18.3 m, Vo = 40 m/s, t = ?.

*April 28, 2016*

**Science**

Z = Sqrt(560^2+1200^2) = 1324.2 Ohms. I = E/Z, Vl = I*Xl. You didn't give the supply voltage, E.

*April 27, 2016*

**Algebra**

X^2 + Y^2 = 25^2, X^2 + (-7)^2 = 625, X^2 = 625-49 = 576, X = 24. Cos A = x/r = 24/25.

*April 27, 2016*

**Physics**

k = 0.8N/0.0050m = 160 N/m. L = 1.5 + 3.5N*1m/160N. = 1.5219 m.

*April 27, 2016*

**Physics**

40o E. to N. = 50o N. t0 E. D = 1000km[50o] + 500km[20o]. X = 1000*Cos50 + 500*Cos20o = Y = 100*sin50 + 500*sin20 = Tan A = Y/X, A = ? = Direction. X/Cos A = Magnitude.

*April 27, 2016*

**pre calc**

Correction: The decay rate is exponential. 50/e^x = 32, e^x = 50/32 = 1.5625, X = 0.446 = kt, K = 0.446/t = 0.446/18 = 0.0248. Mr = M/e^kt = M/e^(0.0248t) = Mass remaining.

*April 27, 2016*

**pre calc**

(50-32)grams/18yrs = 1 Gram/yr. Mr = M-1*T = M-T = 50 - 18 = 32 grams. = Mass remaining.

*April 27, 2016*

**Geometry**

x + 2x + 3x = 180, X = 30o = the Smallest.

*April 27, 2016*

**physics**

K = 2N./(2/100)m = 100 N/m. d = 4N. * 1m/100N = 0.04 m. Work = 2 * 0.04 = 0.08 J.

*April 27, 2016*

**physics**

1. KE = 0.5M*V^2 = 0.5*3*2^2 = 6 Joules. 2. PE = KE, M*g*h = 6, 3*9.8*h = 6, h = 0.204 m. sin30 = 0.204/d, d*sin30 = 0.204, d = 0.408 m. = Distance along the incline.

*April 27, 2016*

**math**

P Dollars @ 6%, 2P Dollars @ 3%, (50,000-3P) @ 5.5 0.06P + 0.03(2P) + 0.055(50,000-3P) = 2165. 0.06P + 0.06P + 2750 - 0.165P = 2165, -.045P = 2165-2750 = -585, P = $13,000 @ 6%. 2P = $26,000 @ 3%. (50,000-39,000) = $11,000 @ 5.5%.

*April 27, 2016*

**physics**

V = Vo + g*t = 0 + 9.8*6 = 58.8 m/s. KE = 0.5M*V^2, M = 0.05 kg.

*April 27, 2016*

**physics**

Range = Vo^2*sin(2A)/g. Vo = 80 m/s, A = 30o, g = 9.8 m/s^2.

*April 27, 2016*

**physics**

V = Vo + a*t = 27.5, 25 + a*20 = 27.5, 20a = 2.5, a = 0.125 m/s^2. = Acceleration of car B. Vo*t + 0.5a*t^2 = Vo*t + o.5a*t^2 + 300, Vo*t-Vo*t + 0.5a*t^2 = 0.5*0.125*20^2 + 300, 0.5a*20^2 = 25 + 300 = 325, 200a = 325, a = 1.625 = Acceleration of car A. Va = Vo + a*t = 25 + 1....

*April 27, 2016*

**math**

I = Po*r*t = 100,000*0.06*30 =

*April 26, 2016*

**geometry**

or 2:48 = 1:24.

*April 26, 2016*

**geometry**

Scale Factor = 4Ft/2In = 2 Ft./In.

*April 26, 2016*

**Pre-Calculus**

A = Po(1+r)^c r = 0.03/n = 0.03/2 = 0.015 = Semi-annual % rate. c = 2Comp./yr. * 10yrs. = 20 Compounding periods(N*t). A = 1000(1+0.015)^20 = $1346.86. Repeat for the remaining values of N.

*April 26, 2016*

**Physics**

V = a*t, V = 57 m/s, t = 3.5 s, a = ?. d = 0.5a*t^2.

*April 25, 2016*

**science**

Work = F*d = 53,000 * 20 =

*April 25, 2016*

**Science- Density**

Density = Weigh per unit volume. Unit means one. Therefore, Density = Weight of one volume of a substance. One volume can be 1m^3, 1cm^3, or 1in^3 depending on which unit you are using. Water has a density of 1 gram per cm^3(1g/cm^3) which means that 1 cm^3 of water weighs 1 ...

*April 24, 2016*

**Physics2**

a. E = 3 * 500 = 1500 Volts. b. Ceq = 120/3 = 40 pF. Q = Ceq*E = 40 * 1500 = 60,000 Pico Coulombs. c. Energy = 0.5Ceq*E^2 = 0.5*40 * 1500^2 =

*April 24, 2016*

**math**

21 Ways to score 15 points.

*April 23, 2016*

**math**

1. 5 Long shots. 2. 4 Long shots, 1 field goal, 1 free throw. 3. 4 Long shots and 3 free throw. 4. 3 Long shots, 3 field goals. 5. 3 Long shots, 2 field goals, and 2 free throws. 6. 3 Long shots, 1 field goal, 4 free throws. 7. 3 Long shots, 6 free throws. 8. 2 long shots, 4 ...

*April 23, 2016*

**Physics**

V^2 = Vo^2 + 2a*d. V = 1.4 rad/s, Vo = 4.5 rad/s, a = -0.5 rad/s^2, d = ?. Note: d is angular distance in radians.

*April 22, 2016*

**Physics**

V^2 = Vo^2 + 2a*d. V = 0, Vo = 36 m/s, d = 414 m, a = ?. a will be negative. F = M*a. W = F*d Joules.

*April 21, 2016*

**Physics**

Po = F*d/t = M*g * V = 101 W. = 101 J/s, 121*9.8 * V = 101, V = 0.085 m/s.

*April 21, 2016*

**Physics**

V^2 = Vo^2 + 2g*h. Vo = 0.8 m/s, g = 9.8 m/s^2, h = 7.8 m, V = ?.

*April 21, 2016*

**Physics**

Work = Fx*d = 2.8*Cos26.8 * 8.3 =

*April 21, 2016*

**Physics**

V^2 = Vo^2 + 2a*d. V = 0, Vo = 9.5 m/s, d = 0.24 m, a = ? F = M*a, M = F/a.

*April 21, 2016*

**Physics**

Fn = M*g + Fap*sin64. g = 9.8 m/s^2, Fap = 11 N.

*April 21, 2016*

**Physics**

M*g = (2.5+4.4)*9.8 = 67.6 N. = Total wt. Fx-Fk = M*a, 19*Cos23.5-1.5 = 6.9*a, 6.9a = 15.9, a = 2.31 m/s^2.

*April 21, 2016*

**Physics**

Fo = ((Vs-Vo)/(Vs+Ve)) * Fe = 480 Hz. (345-0)/(345+Ve) * 560 = 480, 345/(345+Ve) * 560 = 480, 193,200/(345+Ve) = 480, 165,600 + 480Ve = 193,200, 480Ve = 27600, Ve = 57.5 m/s. = Velocity of the emitter or source. v

*April 21, 2016*

**Physics**

Change = 5.22*10^-5/oC*(52-14.4)oC = 1.96*10^-3 m. = 1.96 mm.

*April 21, 2016*

**algebra**

$X @ 9%, $Y @ 12%. Eq1: X + Y = $290,000. Eq2: 0.09x + 0.12y = $31,500. Multiply both sides of Eq1 by 0.12 and subtract Eq2 from Eq1.

*April 20, 2016*

**algebra**

1,2,3,4,5,6. 1,2,3,4. 2,3,4,5. 3,4,5,6. 4,5,6,1. 5,6,1,2. 6,1,2,3. 6 Ways.

*April 20, 2016*

**Math**

20,322*12/.004 = 60,966,000 Sheets. The answer is B.

*April 20, 2016*

**Physics**

Please proof-read your problem.

*April 20, 2016*