Wednesday
September 17, 2014

Posts by henry


Total # Posts: 9,077

physics
1. V = a*t = 1.8m/s^2 * 4.5s. = 8.1 m/s. X = 6.1 m/s. Y = 8.1 m/s. tan A = Y/X = 8.1/6.1 = 1.32787 A = 53o = Direction. 2. V = Y/sinA = 8.1/sin53 = 10.14 m/s.
October 5, 2013

physics
Vo = 20m/s[35o] Xo = 20*cos35 = 16.38 m/s. Yo = 20*sin35 = 11.47 m/s. a. Tr = (Y-Yo)/g = 0-11.47/-10=1.147 s = Rise time. h = Yo*t + 0.5g*t^2 = hmax = 11.47*1.147 - 5*1.147^2 = 6.58 m h = 0.5g*t^2 = 6.58-6 = 0.58 m. 5t^2 = 0.58 t^2 = 0.116 Tf = 0.341 s. = Fall time. Range=Xo*(...
October 5, 2013

Physics
a. Wr = m * g = 500kg * 9.8N/kg = 4900 N. b. a=Fn/m = (13500-4900)/500=17.2 m/s^2
October 5, 2013

physics
V^2 = Vo^2 + 2g*h Vo^2 = -2g*h = -2*-9.8*107 = 2097.2 Vo = 45.8 m/s. V = Vo + gt = 0 @ max. ht. Tr = (V-Vo0/g = (0-45.8)/-9.8 = 4.67 s. = Rise time. Tf = Tr = 4.67 s. = Fall time. T = Tr + Tf = 4.67 + 4.67 = 9.35 s. = Time in air.
October 5, 2013

physics
Wb = m * g = 74kg * 9.8N/kg = 725.2 N. = Weight of box. Fs = u * Wb = 1.1 * 725.2 = 797.7 N. = Force of static friction.
October 4, 2013

Physics
a=F/m = (4*415)/140,000=0.011857 m/s^2
October 4, 2013

math
Cost = $2375 * 0.85 * 0.80 * 0.80=$1292 Discount = 2375 - 1292 = $1083.
October 4, 2013

science
V2 = 1000 * 380/760 * 25/50 e. None of these.
October 4, 2013

PHYSICS
Wc = m * g = 200 N. m * 9.8 = 200 m = 20.41 kg. = Mass of crate. F = 55N.[35o.] 55*cos35 - Fk = m*a 45.05 - Fk = m*0 = 0 Fk = 45.05 = Force of kinetic friction. u = Fk/Wc = 45.05/200 = 0.225
October 3, 2013

PHYSICS
Wb = m * g = 100kg * 9.8N/kg = 980 N. F1 = 980*sin15 = 253.6 N. = Force parallel to the ramp. F2 = 980*cosi5 = 946.6 N. = Force perpendicular to the ramp. Fs = F1 = 253.6 N. @ 15o u = Fs/F2 = 253.6/946.6 = 0.268
October 3, 2013

PHYSICS
Ws = m*g = 150 N. = Weight of sled. m = 150/g = 150/9.8 = 15.31 kg. F1 = 150*sin28 = 70.42 N. = Force parallel to the slope. F2 = 150*cos28 = 132.4 N. = Force perpendicular to the slope. a = F1/m = 70.42/15.31 = 4.60 m/s^2.
October 3, 2013

physics
W1 = m * g = 10kg * 9.8N/kg = 98 N. = Wt. 0f m1. Fs = u * mg = 0.69 * 98 = 67.62 N. = Force of static friction. m2 * g = Fs = 67.62 N. m2 * 9.8 = 67.62 m2 = 6.9 kg.
October 3, 2013

physics
Vo = 15.4m/s[38.7o] Xo = 15.4*cos38.7 = 12 m/s. Yo = 15.4*sin38.7 = 9.63 m/s. Range = Vo^2*sin(2A)/g Range = 15.4^2*sin(77.4)/9.8 = 23.62 m. Range = Xo * T = 23.62 m. Range = 12 * T = 23.62 T = 1.97 s. in air. d=Vr * T = 23.62-17.7 = 5.92 m. to run. Vr * 1.97 = 5.92 Vr = 3.0 m...
October 3, 2013

Physics
See 11:48 PM post.
October 2, 2013

Physics
A. h = 0.5g*t^2 = 0.809 m. 4.9t^2 = 0.809 t^2 = 0.1651 t = 0.4063 s. Xo * t = 18.3 m. Xo * 0.4063 = 18.3 Xo = 45 m/s. = Velocity of the pitch. B. h = 0.5g*t^2 = 5.4 m 4.9*t^2 = 5.4 t^2 = 1.1 Tf = = 1.05 = Fall time of each vessel. Ds = Xo * Tf = 15m/s * 1.05s. = 15.75m. = Dist...
October 2, 2013

Physics
V^2 = Vo^2 + 2g*h V^2 = 0 + 19.6*26.8 = 525.28 V = 22.92 m/s.
October 2, 2013

Physics
V^2 = Vo^2 + 2g*h V^2 = 0 + 20*500 = 10,000 V = 100 m/s.
October 2, 2013

physics
You did not give the angle for F2.
October 2, 2013

Physics
u * F = 7.01 N. 0.44 * F = 7.01 F = 15.93 N.
October 2, 2013

Intermediate Algebra
4x^2 + x - 1. Use Quadratic formula. X = (-B +-Sqrt(B^2-4AC))/2A X = (-1 +-Sqrt(1+16))/8 X = (-1 +-Sqrt(17))/8 X = (-1 +- 4.12)/8 = 0.39, and -0.64
October 2, 2013

Intermediate Algebra
11 1/2 * 11^3 = 23/2 * 11^3 = 23/2 * 1331 = 15,306.5
October 2, 2013

Physics
a. Wr = m * g = 56kg * 9.8N/kg = 549. N = Weight of refrigerator. Fs = u*Wr = 0.7 * 549 = 384 N. = Force of static friction which points in the +x direction. b. F = -384 N.
October 2, 2013

Math
X = The # of $10 bills. 3X = the # of $5. bills. 3x+30 = The # of $1 bills. 10x + 5*3x + 1*(3x+30) = 170 10x + 15x + 3x + 30 = 170 28x = 140 X = 5-$10 bills. 3x = 3*5 = 15-$5 bills. 3x+30 = 3*5 + 30 = 45-$1 bills.
October 1, 2013

physics
a. Wt. = m * g 25kg * 9.8N/kg = 245 N. F1 = Force parallel to the incline. F2 = Force perpendicular to the incline. Q1. F1 = 245*sinA = u*F2 245*sinA = 0.45*245*cosA Divide both sides by 245*cosA: sinA/cosA = 0.45 Replace SinA/cosA with tanA: tanA = 0.45 A = 24.2o = Angle of ...
October 1, 2013

physics
V^2 = X^2 + Y^2 V^2 = 3.8^2 + 1,6^2 = 17 V = 4.12 m/s
October 1, 2013

math
I = Po*r*t = 17,000*0.025*5 = $2125
October 1, 2013

Physics
Correction: h = (0-20^2)/-19.6 = 20.4 m.
October 1, 2013

Physics
1. KE = 0.5m*V^2 = 5*20^2 = 2000 Joules 2. V^2 = Vo^2 + 2g*h = h = (V^2-Vo^2)/2g h = (0-20^20/-19.6 = 20.4 m.
October 1, 2013

interest
I = Po*r*t = 400 Po*(8.5/360)*30days = 400 0.70833*Po = 400 Po = $564.71 4564.71.
September 30, 2013

Physics
a. T=290km/81km/h + 210km/80km/h + 25/60 = 6.62 h. b. V = d/T = (290+210)/6.62 = 75.5 km/h.
September 30, 2013

MATH
P = Po + Po*r*t P = 675 + 675*0.1925*1 = $804.94
September 30, 2013

Geometry
Incomplete.
September 29, 2013

math
b. Amt. = 600*3 + 3200 = $5000 To start with. c. $3200/$ = 600 = 5.3 Months
September 29, 2013

Physics
h = 1.94*sin27.5 = 0.896 m. V^2 = Vo^2 + 2g*h V^2 = 0 + 19.6*0.896 = 17.56 V = 4.19 m/s.
September 29, 2013

physics
See previous post: Sun,9-29-13,4:54 PM.
September 29, 2013

physics
a. V = Vo + g*t = 19 m/s. 39 - 9.8*t = 19 -9.8t = 19-39 = -20 t = 2.04 s. b. V = Vo + g*t = -19 m/s. 39 - 9.8t = -19 -9.8t = -58 t = 5.92 s.
September 29, 2013

physics
a. V^2 = Vo^2 + 2a*d a=(V^2-Vo^2)/2d = (15^2-0)/250=0.9 m/s^2 b. V = Vo + a*t t = (V-Vo)/a = (15-0)/0.9 = 16.67 s.
September 29, 2013

physics
Tr = 0.5 * 4.84 = 2.42 s. = Rise time. V = Vo + g.t = 0 @ max ht. Vo - 9.8*(2.42) = 0 Vo = 23.72 m/s. = Initial velocity. h = Vo*t + 0.5g*t^2 h = 23.72*2.42 - 4.9*2.42^2 = 28.7 m.
September 29, 2013

physics
See previous post.
September 29, 2013

physics
a. F = 7 + 10 = 17 N. b. F = 10-7 = 3 N. c. F1 = 7N[45o]. F2 = 10N[105o]. X = 7*cos45 + 10*cos105 = 2.36 N. Y = 7*sin45 + 10*sin105 = 14.6 N. tanA = Y/X = 14.6/2.36 = 6.18644 A = 80.8o Fr=Y/sinA = 14.6/sin80.8=14.8 N.[80.8o] = Resultant force. d. Fr = 7[160o] + 10[160o] = 17N[...
September 29, 2013

Grade 12 physics
F1 = 15N[66o],CCW. F2 = Pull South. F3 = Pull West. a. X = 15*cos66 + F3 = 0 F3 = -15*cos66 = -6.10 N. Y = 15*sin66 + F2 = 0 F2 = -15*sin66 = -13.7 N. b. X = 15*cos66-6.10 = 0 Y = 15*sin66 = 13.7 N.=13.7N Fn = X + Yi = 0 + Yi = 13.7i=13.7N[90o]
September 29, 2013

physics
Fa + Fb + Fc = 2.33N[S12.2W]
September 29, 2013

physics
Fa = 2.3N[235o],CCW. Fb = 3.6N[104o],CCW. Fc = 4.2N[294o],CCW. X=2.3*cos235+3.6*cos104+4.2*cos294 = -0.482 N. Y=2.3*sin235+3.6*sin104+4.2*sin294= -2.28 N. tan Ar = Y/X = -2.28/-0.482 = 4.62215 Ar = 77.8o = Reference angle. A = 77.8 + 180 = 257.8o CCW = 12.2o W of S. Fr = Y/...
September 29, 2013

maths
P = Po(1+r)^n n = 4Comp./yr * 5yrs. = 20 Compounding periods. P = 10,000(1+r)^20 = $20,000 Divide both sides by 10,000: (1+r)^20 = 2 Take Log of both sides: 20*Log(1+r) = Log 2 Divide both sides by 20: Log(1+r) = 0.015051 1+r = 10^0.015051 = 1.035265 r = 1.035265-1 = 0.035265...
September 29, 2013

Physics
a. 8.1[52o] + 8[180o] X = 8.1*cos52 + 8*cos180 = 4.99 Units Y = 8.1*sin52 + 8*sin180 = 6.38 Units. Mag. = Sqrt(4.99^2+6.38^2 = 8.1 Units tanA = Y/X = 6.38/4.99 = 1.27856 A = 51.97o = Direction. b. 8.1[52o] - 8[180o] Subtract and use same procedure as "a".
September 29, 2013

physics
Vf = 3.2m/s + 0.68*8 = 8.64 m/s.
September 28, 2013

physics
Incomplete.
September 28, 2013

physics
h = 168 - 0.5g*t^2 h = 168 - 4.9*2.24^2 = 143.4 m
September 28, 2013

math
(x+y+3y)/2 = 3x 6x = x+4y 4y = 5x Y = 5x/4
September 28, 2013

physics
F = m*a = 13 N. 36*a = 13 a = 0.361 m/s^2 d = 0.5a*t^2 = 0.5*0.361*4.5^2 = 3.66 m.
September 28, 2013

physics
Vo = 29m/s[36.9o] Xo = 29*cos36.9 = 23.2 m/s. Yo = 29*sin36.9 = 17.4 m/s. a. h = Yo*t + 0.5g*t^2 = 10 m 17.4*t - 4.9t^2 = 10 -4.9t^2 + 17.4t - 10 = 0. Use Quad. Formula. t = 0.72, and 2.83 s. b. X = Xo = 23.2 m/s. = Hor. component of velocity , and does not change. c. Y = Yo...
September 28, 2013

Physics
When t = 0, x = 0.
September 27, 2013

dma040
Do you mean V = (1/3)*ah? If so, V = ah/3 Multiply both sides by 3/a: h = 3V/a
September 27, 2013

Physics
L = (V^2-Vo^2)/2g a. L = (15^2-4.7^2)/19.6 = 10.4 m. b. h = L*sin10 h = 10.4*sin10 = 1.8 m. h = Vo*t + 0.5g*t^2 = 1.8 4.7t + 4.9t^2 = 1.8 4.9t^2 + 4.7t - 1.8 = 0 t = 0.293 s. Use Quadratic Formula.
September 27, 2013

Crossing a River in min time
TanA = (1km/h)/15km/h = 0.066666 A = 3.8o E. of N. d = 1.17/cos3.8 = 1.173km. = Distance boat must travel. Vb = 15/cos3.8 = 15.033 km/h d = V*t = 1.173 km 15.033t = 1.173 t = 0.078028 h = 4.68 Min.
September 27, 2013

physics
a. OA = 0.5a*t^2 = 25 m. 0.5a*7^2 = 25 0.5a*49 = 25 a = 1.02 m/s^2 b. V = a*t = 1.02 * 7 = 7.14 m/s. c. AB = (V^2-Vo^2)/2a AB = (15^2-7.14^2)/2.04 = 85.3 m.
September 24, 2013

physics
a. V = Vi + g*t b. d = Vi*t + 0.5g*t^2 c. V = -Vi + g*t. d = -Vi*t + g*t
September 24, 2013

Phsyics
Vo = 30m/s[80o] Yo = 30*sin80 = 29.54 m/s. hmax = (V^2-Vo^2)/2g hmax = (0-29.54^2)/-19.6 = 44.52 m Tr = -Vo/g = -29.54/-9.8 = 3.0 s = Rise time, Tf = 5-3 = 2 s. = Fall time. h = ho - 0.5g*t^2 h=44.52 - 4.9*2^2 = 24.92 m. after 5 s. 4.9*2^2 = 19.6
September 24, 2013

physic
V^2 = 30^2 + 5^2 = 925 V = 30.4 km/h.
September 24, 2013

Physics
Vo = 36km/h = 36000m/3600s = 10 m/s. V^2 = Vo^2 + 2g*h h = (V^2-Vo^2)/2g h = (0-10^2)/-19.6 = 5.0 m.
September 23, 2013

Physics
See previous post: Tue,1-18-11,6:56 PM.
September 23, 2013

physics
Correction: F2 = mg*cosA.
September 23, 2013

physics
mg = 667.5 N. F1 = mg*sinA = 667.5*sin38 = 411 N = Force parallel to the hill. F2 = mg*sinA= 667.5*cos38 = 526 N = Force perpendicular to the hill. Fs = u*F2 = 0.4 * 526 = 210.4 N = Force of static friction. Yes, because F1 is greater than the forceof s tatic friction, Fs.
September 23, 2013

Physics
a. V2 = T2/T1 * P1/P2 * V1.
September 23, 2013

physics
Vo = 18.9m/s[47o] Xo = 18.9*cos47 = 12.9 m/s. Range = Vo^2*sin(2A)/g Range = 18.9^2*sin94/9.8 = 36.4 m. Range = Xo * t = 36.4 m. 12.9 * t = 36.4 t = 2.82 s. in flight. d = 54.4-36.4 = 18 m To run in 2.82 s. Speed = d/t = 18m/2.82s = 6.38 m/s.
September 23, 2013

Physics
Vo = 15m/s[75o] Xo = 15*cos75 = 3.88 m/s. Range = Vo^2*sin(2A)/g Range = 15^2*sin(150)/9.81 = 11.47 m. d = 0.5a*t^2 = 11.47 m. 0.5a*1.03^2 = 11.47 0.53a = 11.47 a = 21.6 m/s^2.
September 22, 2013

Physics
0.4.9*t^2 = h t^2 = h/4.9 t = sqrt (h)/2.21 = Fall time. S = Vx * t
September 22, 2013

Physics
P = mg*d/t = 600 * 1.2/1.5 = 480 J/s = 480 Watts.
September 22, 2013

physics
See previous post: Sun,9-22-13,8:57 PM.
September 22, 2013

physics
a = (V-Vo)/t = (34-10)/10 = 2.4 m/s^2. Fn = m*a = 1570 * 2.4 = 3768 N.
September 22, 2013

physics
See previous post: Tue,1-18-11,6:56 PM.
September 22, 2013

Physics
a = (V-Vo)/t = (10-(-50))/15 = 4 m/s^2.
September 22, 2013

Physics
A. h = 0.5g*t^2 = 4.9*15^2 = 1103 m. B. d = 290m/s * 15s = 4350 m. C. Over the island.
September 22, 2013

physics
See previous post: Sat,9-21-13,11:52 PM.
September 22, 2013

physics
Da = 204 + Db Da = 22.9t = 204 + 18.6t 22.9t-18.6t = 204 4.3t = 204 t = 47.44 s. To catch up.
September 22, 2013

physics
d = 0.5a*t^2 = 0.725 * 63.7^2 = 2942 Rad
September 22, 2013

physics
d1 + d2 = 5.16 m. (Vo*t+0.5g*t^2 ) + (Vo*t+0.5g*t^2=5.16 (8.67t-4.9t^2) + (8.67*t+4.9*t^2 = 5.16 8.67t + 8.67t = 5.16 17.34t = 5.16 t = 0.298 s. Note: 4.9t^2-4.9t^2 = 0 d1 = 8.67*0.298 - 4.9*0.298^2 = 2.14 m Above gnd. = The point where they meet.
September 21, 2013

Physics
Incomplete and unclear.
September 21, 2013

Physics
A = 45.6[51.2o]. B = 23.6[32.8o] C = 34[270o] A-B+C = 45.6[51.2o]-23.6[32.8o]+34[270] X = 45.6*cos51.2-23.6*cos32.8+34*cos270= 8.74. Y = 45.6*sin51.2-23.6*sin32.8+34*sin270= -11.2 tanAr = Y/X = -11.2/8.74 = -1.28146 Ar = -52o = Reference angle. A = -52 + 360 = 308o. = ...
September 21, 2013

physics
d = Xo * T = 2700 m. 520T = 2700 T = 5.19 s.
September 21, 2013

math
1. Real Numbers.
September 20, 2013

maths
5F = 250 F = 50 Females. F = 250 - 50 = 200 Females needed.
September 20, 2013

maths
Scale = 1:200,000? d = (200000/1) * 3cm = 600,000 cm. = 6000 m. = 6 km.
September 20, 2013

Physics
Y/X = 56/-25.5 = -2.19608 Ar = -65.5o = Rerence angle. A = -65.5 + 180 = 114.5o = Direction. Mag. = Y/sinA = 56/sin114.5 = 61.5 Units NOTE: If you draw the vector diagram showing 56 on the positive Y-axis and -25.5 on the negative X-axis, you can see that the Direction lies ...
September 20, 2013

Physics
See your previous post.
September 20, 2013

Physics
A + B = -15 29 + B = -15 B = -15-29 =-44 Units and points in negative Y direction.
September 20, 2013

Physics
B. d = 0.5a*t^2 = 2.27*8.43^2 = 161.3 m. C. V = a*t = 4.53*8.43 = 38.2 m/s. D. 3.62*8.43 = 30.5 m/s.
September 20, 2013

Physics
d1 = 0.5a*t^2 = 1.81*1.01^2 = 1.85 m. Head start. V1 = a*t = 3.62*1.01 = 3.66 m/s. d2 = 0.5a*t^2 = 1.85 + V1*t + 0.5a*t^2 2.27t^2 = 1.85 + 3.66*t + 1.81t^2 2.27t^2-1.81t^2 -3.66t - 1.85 = 0 0.46t^2 - 366t - 1.85 = 0 t = 8.43 s. To catch up.
September 20, 2013

physics
F = m*a a = F/m = 4.9*10^5/7 = 7*10^4 m/s^2 t = (V-Vo)/a = (4000-0)/70,000=0.0571 s.
September 20, 2013

physics
Xo = 180*cos34 = 149.2 m/s.
September 20, 2013

physics
sinA = 15%/100% = 0.15 A = 8.63o
September 20, 2013

physics
tanAr = Y/X = 325/-445 = -0.73034 Ar = -36o = Reference angle. A = -36 + 180 = 144o CCW = 54o W. of N.
September 20, 2013

physics
D = X^2 + Y^2 = 26.7^2 X^2 + 25^2 = 26.7^2 Solve for X.
September 19, 2013

Physics
a = (V^2-Vo^2)/2d a = (21^2-35^2/0.08 = -9800 m/s^2. V = Vo + a*t = 21 m/s. 35 + -9800t = 21 t = 0.001429 s. = 1.429 ms.
September 19, 2013

Physics
d = Vo*t + (V^2-Vo^2)/2a d = 24.4*1 + (0-24.4^2)/-16 = 61.6 m.
September 19, 2013

Physics
Incomplete.
September 19, 2013

Mechanics
Correction: a = (26-0)/0.008 = 3250m/s^2
September 19, 2013

Mechanics
a = (V-Vo)/t = (0-26)/0.008s = 3250m/s^2 F = m*a = 0.425 * 3250 = 1381.3 N.
September 19, 2013

Mechanics
Momentum = m*V = 0.058*51 = 2.96
September 19, 2013

Physics
See previous post: Wed,9-18-13,8:10 PM.
September 19, 2013

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