# Posts by Henry

Total # Posts: 13,439

**Physics**

Range = Vo^2*sin(2A)/g. Range = 65^2*sin(2*37)/9.8 = 414.4 m.

**Physics**

V = Vo + a*t. 55 = 70 + a*25, a = ?.

**Physics**

V = 68mi/72min * 60min/h =

**Physics**

V^2 = Vo^2 + 2g*h. 0 = 69^2 - 19.6h, h = ?. V = Vo + g*t. 0 = 69 - 9.8t, t = ?.

**physics**

V^2 = vo^2 + 2g*h. V^2 = 0 + 19.6*27, V = 23 m/s.

**Math**

(x-2)/x > 1/2. 2x-4 > x, X > 4. Let x = 5. (5-2)/5 = 3/5.

**math**

A diagram of the problem: 1. Draw a rectangle with the longest sides hor. 2. Draw a hor. line through the ver. sides to form two rectangles. 3. Label the ver. sides of the lower rectangle h1(15m) and the ver. sides of the top rectangle h2. 4. Draw a diagonal from the upper ...

**math**

Tan 17 = h1/d. Tan 17 = 15/d, d = 49.1 m. = Distance between the buildings. Tan32 = h2/d. Tan32 = h2/49.1, h2 = 30.7 m. = ht. from window of 1st bldg. to top of 2nd bldg. h = h1+h2 = 15 + 30.7 = 45.7 m. = ht. of 2nd bldg.

**Math**

Yes! -9(x-63) = x + (-49) = x-49.

**PHYSICS**

A window washer pulls herself upward using the bucket-pulley apparatus.. Part A) How hard must she pull downward to raise herself slowly at constant speed? The mass of the person plus the bucket is 80 kg . Part B) If she increases this force by 16 %, what will her acceleration...

**physics**

The cable supporting a 2150-kg elevator has a maximum strength of 2.2×104 N . What maximum upward acceleration can it give the elevator without breaking?

**Physics**

1. V^2 = Vo^2 + 2a*d. (3*10^6)^2 = 0 + 2a*0.15, a = ?. 2. F = M*a, a = F/M = 4.9/0.5 =

**maths**

(75+82+90+X)/4 = 85. X = ?.

**physics**

See previous post.

**physics**

V = pi*r^2*(h2-h1). V = 3.14*6^2*(135-120) = 1696 cm^3.

**Algebra**

1. (3,2), (1,-4) m = (y2-y1)/(x2-x1) = (-4-2)/(1-3) = -6/-2 = 3. 2. (-2,4), (-4,6). m = (6-4)/(-4-(-2)) = 2/-2 = -1. 3. (7,4), (-5,-2). m = (-2-4)/(-5-7) = -6/-12 = 1/2. Y = mx + b 4 = (1/2)7 + b, b = 1/2. Y = (1/2)x + 1/2. 4. (1,4), (2,-8). m = (-8-4)/(2-1) = -12, Y = mx + b...

**Math**

3pizzas/4bro. = 3/4 Pizza/bro.

**Physics**

V1 = a1*t1 = 1.76 * 20 = 35.2 m/s. d1 = 0.5a1*t1^2 = 0.88*20^2 = V2 = V1 + a*t = 35.2 - 5.93*5 = 5.55 m/s. The 5-second deceleration is not enough to bring the car to a full stop. d2 = V1*t + 0.5a*t^2. d2 = 35.2*5 - 0.5*5.93*5^2 = d = d1+d2 =

**algebra**

14x -3 y to the negative 4 / 2x5 y to the negative 2 how do you do this

**math**

1. I = Po*r*t = 1200*(0.105/12)*3. 2. P = Po + Po*r*t. P = 1200 + 1200*0.0775*2 = 3. 100%-20% = 80% financed. Po = 0.80 * 69,500 =

**Math**

4. 30/80 = 6/16. Not 6/18.

**Math**

1. 4/20 = 1/5. Not 1/6.

**math**

a. 1957 total CDs. X pop CDs. x-256 hip-hop CDs. (x-256)/3 country CDs. x + (x-256) + (x-256)/3 = 1957. Multiply both sides by 3 and solve for x. c. Country CDs/3.

**Physics**

V2 = V1 + a*t. 60 = 0 + a*4, a = 15 m/s^2. d = V1*t + 0.5a*t^2. V1 = 0, t = 4 s., a = 15 m/s^2, d = ?.

**physics**

Mb*V1 + Ma*V2 = Mb*V3 + Ma*V4. 5*3 - 10*3 = 5*V3 + 10*2, -15 = 5V3 + 20, V3 = -7 m/s = 7 m/s to the left.

**Science**

Incomplete.

**Science**

A. d = Vo*t + 0.5a*t^2. d = 0 + 1*30^2 = B. V = a*t.

**physics**

Tan A = (-3.50)/116.5 = -0.030043, A = -1.72o = 1.72o S. of E. Tan1.72 = d/153, d = 4.59 m.

**Physics**

Range = Vo^2*sin(2A)/g. 2.4 = 7^2*sin(2A)/9.8. A = 14.7o. = Minimum launching angle. Max. range occurs at 45o: Range = 7^2*sin(2*45)/9.8 = 5 m., max. Range of launch angles = 14.7 t0 45o.

**algebra**

t = 4/8 * 32h =

**physics**

2. Continued. d = V*t, V = 3*10^5 km/s, t = ?.

**physics**

1. 10^56/10^35 = 2. d = 3.3AU * 1.499*10^8km/AU =

**Pre Cal**

A ) B + C = 180. A + 62 + 48 = 180, A = 70o. sinB/b = sinA/a. b = ?.

**biology**

1)Can you suggest reasons why a phylogeny based on molecular evidence and a phylogeny based on morphology and other evidence might not be exactly the same? 2) Zoologist worldwide are sequencing a mitochondrial gene CO1 (cyctochrome c oxidase subunit), which is found in all ...

**Physics**

M*g = 300 * 9.8 = 2940 N. = Wt. of furniture. Fk = Force of kinetic friction. F1 = 45 N. F2 = 80*Cos25 = 72.5 N. F1+F2 - Fk = M*a. Fk = ?.

**Physics**

a. V = Vo + a*t. V = 0, Vo = 15 m/s, t = 0.3 s., a = ?. a will be negative. b. F = M*a. F will be negative.

**physics**

F = 2N/0.2cm * 2cm = 20 H. Work = F*d.

**math**

X tickets sold. x/6 children's tickets. 40 seniors tickets. X/2 adult tickets. x/6 + 40 + x/2 = X. x/6 + 40 + 3x/6 = x, 4x/6 - x = -40, -2x/6 = -40, X = 120. x/6 = 120/6 = 20. x/2 = 120/2 = 60 2*20 + 3*40 + 6*60 = $520 Collected.

**math**

Correction: Ignore the "10".

**math**

10 100ft^2/2 = 50 ft^2/sq. s^2 = 50, s = 7.071 ft. 7.071ft/side * 8sides = 56.57 ft = total required. But we have only 56 ft.

**math**

At = Ag + Arg. At = 6 + Arg, We need to know the dimensions of the area surrounding the rose garden. Then we could calculate At, the total area which leaves only one unknown(Arg), the area of the rose garden.

**Science**

d = V*t.

**Math**

Flour/Milk = Y/X = 5/4. a. Yes. b. Y/X = 5/4, Y/14 = 5/4, Y = ?.

**Math**

See previous post: Wed, 1-25-17, 8:22 P.M.

**physics**

Disp. = -34i + 117 + 64.5i + 28.5 = 145.5 + 30.5i. Magnitude = sqrt(145.5^2+30.5^2) =

**Math**

Wed.: d = r*t1 = 50mi/h * (43/60)h = 35.83 mi. Thu.: t2 = d/r = 35.83/68 = 0.527 h. = 31.6 min. t1-t2 = 43-31.6 = 11.4 min = Time saved.

**Physics**

40m/1min = 40m/60s = 0.667 m/s.

**Math**

5/20 = 1/4. A. = 1/4. D. 25/10 = 1/4.

**physics**

The positive and negative plates of a parallel-plate capacitor have an area of 1.05 cm by 1.05 cm. Their surface charge densities are +1.00×10-6 C/m2 and -1.00×10-6 C/m2, respectively. A proton moving parallel to the plates enters the middle of the space between ...

**science**

The system is in equilibrium: 30o W. of N. = 120o CCW. T1*Cos120 = -T2*Cos60. T1 = T2. T1*sin120 + T2*sin60 = -(-10) = 10. T2*sin120 + T2*sin60 = 10, 0.866T2 + 0.866T2 = 10, T2 = 5.77 N. T1 = T2 = 5.77 B.

**applied mechanics**

Vo = 72000m/3600s = 20 m/s. V = Vo + a*t = 0. 20 + a*5 = 0, a = -4 m/s^2. V^2 = Vo + 2a*d. V = 0, Vo = 20 m/s, a = -4 m/s^2, d = ?.

**Algebra**

K = (M2-M1)/(d2-d1) = (30-12)/(18-15) = 6 kg/cm . d = (12kg/6kg) * 1cm = 2 cm. L + 2 = 15, L = 13 cm.

**Science**

F = m*g in Newtons(N). Work = F*d in Joules.

**Math**

Assuming simple interest: P = Po + I = Po + Po*r*t. P = 6500 + 6500*0.09*4 = 6500 + 2340 = $8840 = Total amt. paid. I = P=Po =

**Math**

a. d = r*t. b. t = d/t. Eq1: t1 + t2 = 4 1/3 h. = 13/3 h. Eq2: 60t1 + 90t2 = 350 km. Solve the 2 Eqs simultaneously: -60t1 - 60t2 = -260 +60t1 + 90t2 = 350 sum: 30t2 = 90, t2 = 3 h. t1 + 3 = 13/3, t1 = 4/3 = 1 1/3 h. d1 = 60 * 4/3 = d2 = 90 * 3 =-

**Geometry**

As = 2pir^2 + pi*2r*h. As = (6.28*8^2) + (3.14*16*24) = 1608 m^2.

**Math**

a. 3:05, and 3:10. b. 5:00, and 6:05. c. 10:00, and 11:00.

**Maths**

c = X cm. a = x+20 cm. b = x+20 + 50 cm. a + b + c = 270. x+20 + x+20+50 + x = 270. X = ?. b = x+20+50.

**physics**

T = 2pi*sqrt(L/g). pi = 3.14., L = 1.25 m., g = 9.8 m/s^2.

**math**

a = b. x+2y = -2x+6y+1. Eq1: 3x-4y = 1. a + b + c = 28. x+2y -2x+6y+1 + 4y = 28. Eq2: -x+12y = 27. Add Eq1 and Eq2, solve for X, and Y: +3x - 4y = 1 -3x + 36y = 81(3*Eq2). sum: +32y = 82, Y = 41/16. In Eq1, replace Y with 41/16, and solve for X: 3x - 4*41/16 = 1, X = 15/4. X...

**Mathematics**

1. P1 = Po + Po*r*t. P1 = 12,500 + 12,500*0.12*3 = 2. P2 = Po(1+r)^n. Po = 12,500, r = 0.10. n = 1comp./yr. * 3yrs. = 3 compounding periods. P1-P2 =

**math**

Eq1: 4x + 2y = -2. m1 = -A/B = -4/2 = -2. m2 = m1 = -2. P2 = (-5,-7). Y = mx + b = -7, -2x + b = -7, b = -7+2x = -7 + 2(-5) = -17. Eq2:Y = -2x - 17.

**physical science**

Fr = -300 + 150 = -150 N. = 150 N. to the left.

**math**

C = pi*D = 3.14 * 25 = 78.5 in. 5,280ft/mi * 12in/ft. * 360o/78.5in * 295mi =

**Math**

The altitude(ht.) bisects the vertical angle and the base: 118/2 = 59o. Tan(90-59) = h/5. h = ?.

**Math**

Concentration = 6*120mg/60mls =

**Physical Science.**

Displacement is the straight-line distance from the end point to the starting point. The path traveled might not be a straight line. Displacement =< Distance traveled.

**Algebra**

T = T1*T2/(T1+T2) = 16*15/(16+15) =

**Math**

B.

**math**

0nes place = 9. tens place = X. hundreds place = X+1. x + x+1 = 11. X = 5. 659 blocks.

**Algebra 2**

2 People: 60boxes/10min . = 6 boxes/min. 6 People: (6/2) * 6 = 18 boxes/min. T = 120boxes * 1min/18boxes = 6.67 min.

**dynamics**

V1 = 400m/20s = 20 m/s. V2 = 400m/30s = 13.33 m/s. a = (V2-V1)/(T2-T1) = (13.33-20)/(30-20) = -0.667 m/s^2. V2 = V1 + 2a*d. 13.33 = 20 - 2*0.667*d. d = ?.

**physics**

a. M1*V1 + M2*V2 = 2.9*5.4 - 1.5*1.4 = 13.6

**physics**

V = Vo + a*t. -1.33 = 0 + a*0.96, a = -1.33/0.96 = -1.39 m/s^2. F = M*a = 53.8 * (-1.39) = -74.5 N.

**math**

a. At =8*11= 88 in^2 = Total area. Ac = pi*r^2 = 3.14 * 1.5^2 = 7.07 in^2. = Area of each circle. As = 3 * 3 = 9 in^2. = Area of a 3 in square in which the circle can be inscribed. At/As = 88/9 = 9.78 or 9 = The number of squares = the number of circles that can be cut. b. 9Ac...

**Grade 6, percentage**

At beginning of year: X members in art club. 0.4X boys. 0.6X girls. In middle of year: 0.75 * 0.6X = 0.45X girls remaining. 0.4X+8 boys remains. 0.45x + 0.4x+8 = 42. X = 40 At beginning of year.

**maths**

Insufficient INFO.

**MATH**

200paces/4sides = 50 paces/side. 50paces/side * 40cm/pace = 2000 cm/side.

**Math- fractions**

So, we find a common denominator for the two fractions: 2/3 = 8/12, and 3/4 = 9/12.

**math**

I = Po*r*t = 8000*0.07*5 =

**Grade 6, percentage**

X members at first. 0.8 * x = 0.8x Male. x - 0.8x = 0.2x Female. After 450 members left: 0.75*0.8x + 0.5*0.2x = x-450. 0.6x + 0.1x - x = -450, X = 1500.

**Physics**

64.8o W of N = 154.8o CCW. 22.4o W of N. = 112.4o CCW. M1*V1 + M2*V2 = = M1*V3 + M2*V4. 0.4*3.57m/s[154.8o] + 0.45*5.46m/s[90o] = 0.4*4.28m/s[112.4o] + 0.45*V4. 1.43m/s[154.8] + 2.46m/s[90o] = 1.71m/s[112.4] + 045V4, -1.29+0.609i + 2.46i = -0.652+1.58i + 0.45V4, -1.29 + 3.07i...

**Physics**

L = V*T. 1.3 = 2.5*T, T = ?

**algebra**

Divide numerator and denominator by 5: (x-1)/(2x^2-5x+3). Factor the denominator: A*C = 2*3 = 6 = (-2)*(-3), 2x^2 - (2x+3x) + 3 = 0, (2x^2-2x) - (3x-3) = 0, 2x(x-1) - 3(x-1) = 0, (x-1)(2x-3) = 0, (x-1)/(x-1)(2x-3) = 1/(2x-3).

**maths**

Option 1: P = Po + Po*r*t. P = 12,000 + 12,000*(0.08/12)*9 = 12,000 + 720 = $12,720. I = $720. Option 2: Ar = Ab-Ab*r*t. Ar = 12,000-12,000*(0.07/12)*9 = 12,000 - 630 = $11,370 = Amt. received. I = $630. Gary should choose Option 2.

**Physics**

See previous post: Wed, 1-11-17, 12:49 PM.

**Physics**

F = M*g = (80+20)*9.8 = Work = F*d.

**Physics**

d = 0.5g*t^2 = 4.9*1^2 = 4.9 m.

**Trig/PreCalc**

Vr = 425mph[160o] + 75mph[200o]. X = 425*cos160+75*cos200 = -470 mph. Y = 425*sin160+75*sin200 = 120 mph. Tan A = Y/X = 120/-470 = -0.25532. A = -14.3o. = 14.3o N. of W. = The direction. Vr = -470/-Cos14.3 = 485 mph. = Resultant speed.

**Science**

F=M1*a1. M1 = F/a1 = 400/2 = 200 kg. M2 = F/a2 = 400/13 = 30.8 kg. a = F/(M1+M2).

**Physics**

The two numbers cannot be added directly, because they are 90o out of phase: V = 300 + 400i. You only want the magnitude: V = sqrt(300^2+400^2) = 500 m/s.

**Physics**

M*g = 30 * 9.8 = 294 N. Fp = 294*sin30 = 147 N. = Force parallel with slide. Fn = 294*cos30 = 254.6 N. = Force perpendicular to the ride = Normal. Fk = u*Fn = 0.15 * 254.6 = 38.2 N. = Force of kinetic friction. Fap = 200 N. = Force applied. Fap-Fp-Fk = M*a. 200-147-38.2 = 30*a...

**Physics**

a,b. M1*V1 + M2*V2 = M1*V3 + M2*V4. 1*5 + 1*0 = 1*4[37o] + 1*V4. 5 = 4[37o] + V4, V4 = 5-4[37O], V4 = 5-4*Cos37-4*sin37 = 5-3.19-2.41i = 1.81 - 2.41i = 3.01m/s[-53.1o] = 3.01m/s[53.1o] S. of E. = Velocity and Direction. c. A1+A2 = 37 + 53.1 = 90.1o.

**Math**

D. 12/15 = 4/5, 30/50 = 3/5. The ratios must be equal to form a true proportion.

**physics**

M*g = 225, M = 225/g = 225/9.8 = 23 kg. F = M*a, a = F/M = 14.5/23 = 0.630 m/s^2.

**physics**

The system is in equilibrium: T1*sin15.4 + T2*sin A = +253. 459*sin15.4 + T2*sin A = 253, 121.9 + T2*sin A = 253. T2 = (253-121.9)/sin A = 131.1/sin A. -T1*Cos15.4 + T2*Cos A = 0, -459*Cos15.4 + T2*Cos A = 0. T2*Cos A = 459*Cos15.4 = 442.5, (131.1/sin A)Cos A = 442.5, 131.1*...

**Science**

M/W.

**Physics**

Density = 100g/150cm^3 = 0.667 g/cm^3.

**Physics**

Vb = 0.85 * 250 = 212.5 cm^3 = Vol. below surface. = Vol. of water displaced. V*D = 212.5cm^3 * 1g/cm^3 = 212.5 grams of water displaced. Upthrust = M*g = 0.2125 * 9.8 = 2.08 N.

**Math**

8/(2/3) = 8 * 3/2 = 12. pieces.