Tuesday

October 21, 2014

October 21, 2014

Total # Posts: 9,313

**math**

d = 1in/Xmi. * M mi = M/X inches.
*August 18, 2014*

**math**

P = Po + 0.5Po = $81. 1.5Po = 81 Po = $54 = Initial price or Cost.
*August 18, 2014*

**geometry**

9<n<14 Values of n: 10, 11, 12, 13. Sum = 10+11+12+13 = 46 cm. 5<n<9 Values of n: 6, 7, 8. Sum = 6+7+8 = 21 cm. n = 5 cm(Isosceles Triangle). n = 9 cm(Isosceles Triangle). Sum Total=5+6+7+8+9+10+11+12+13 = 81 cm.
*August 17, 2014*

**mat**

6.5Ft/3in = 2.17Ft/in Depth = 5 + 2.17x X = The # of inches of rain.
*August 17, 2014*

**Physics**

Yes, I'm glad it didn't fall on MY head!
*August 17, 2014*

**Physics**

Mass = 20kg?(Check for error). a = g = 9.8 m/s^2 F = m * g
*August 17, 2014*

**physics**

Vo = 84m/s[45o]. Dx = Vo^2*sin(2A)/g=84^2*sin90/9.8=720 m with zero wind. (720-630)/720 * 100% = 12.5% Decrease.
*August 17, 2014*

**math**

d^2 = X^2 + Y^2 = 4^2 + 5^2 = 41 d = 6.4 km. = Shortest distance to his home.
*August 17, 2014*

**Geometry**

One side = L units. 2nd side = 3L units. 3rd side = 15 units. 3L < 15 L < 5 L = 4 = Largest possible integer. 3L = 3*4 = 12. P = 4 + 12 + 15 = 31 = Max. possible perimeter.
*August 15, 2014*

**trig**

Angular velocity is usually given in rad/s., deg./s, or rev/min. So please check your INFO.
*August 15, 2014*

**Trigonometry**

12.4rev/ride * 3rides = 37.2 Revs. A = 37.2rev * 360Deg/rev = 13,392o = 233.6 Radians. Circumference=pi*2r = 3.14*36.6=114.92 m. d = 37.2rev * 114.92m/rev = 4275.2 m. traveled.
*August 15, 2014*

**Physics**

Vo = 36km/h = 36,000m/3600s = 10 m/s. V = 9km/h = 9000m/3600s = 2.5 m/s. a = (V^2-Vo^2)/2d a = (2.5^2-10^2)/300 = -0.3125 m/s^2. d = (V^2-Vo^2)/2a d = (0-2.5^2)/-0.6250 = 10 m. Further.
*August 15, 2014*

**physics**

a=(V^2-Vo^2)/2d=(0-(20^2))/30=-13.3m/s^2
*August 14, 2014*

**High School Physics**

X = 10 m/s Y = 20 m/s V^2 = X^2 + Y^2 V^2 = 10^2 + 20^2 = 500 V = 22.4 m/s = Resultant velocity. a = (V-Vo)/t = (22.4-0)/t = 22.4/t m/s^2 d = 0.5*a*t^2 = 150 0.5*(22.4/t)*t^2 = 150 m (11.2/t)*t^2 = 150 11.2t = 150 t = 13.4 s.
*August 12, 2014*

**Math**

C = 75 + 5f. C is the dependent variable. It depends on the value of f.
*August 12, 2014*

**pHYSICS`**

m*g = 50kg * 9.8N/kg = 490 N. = Wt. of cart. Fk = u*mg = 0.2 * 490 = 98 N. = Force of kinetic friction. a=(V-Vo)/t = (0.90-0)/2.8 = 0.321 m/s^2/ F-Fk = m*a F - 98 = 50*0.321 = 16.07 F = 16.07+98 = 114.1 N.
*August 11, 2014*

**physics**

T = 50min * 1h/60min = 5/6 h. T = t1 + t2 = 5/6 h. d/(Vb-Vs) + d/(Vb+Vs) = T 8/(Vb-2.8) + 8/(Vb+2.8) = 5/6 LCD = (Vb-2.8)(Vb+2.8). (8(Vb+2.8)+8(Vb-2.8))/(Vb-2.8)(Vb+2.8)= 5/6. (8Vb+22.4+8Vb-22.4)/(Vb-2.8)(Vb+2.8)=5/6 16Vb/(Vb-2.8)(Vb+2.8) = 5/6 Cross multiply: 96Vb = 5(Vb-2.8...
*August 10, 2014*

**Math**

Eq1: 2r - 7s = -6 Eq2: 7r - 2s = 32 Multiply Eq1 by (-7) and Eq2 by 2; then add: -14r + 49s = 42 +14r - 4s = 64 Sum: 45s = 106 S = 2 16/45 = 106/45. In Eq1, replace s with 106/45: 2r - 7*(106/45) = -6 2r - 742/45 = -6 Multiply by 45: 90r - 742 = -270 90r = -270 + 742 = 472 r...
*August 10, 2014*

**Algebra**

15x(x+2) + 1(x+2) Factor out x+2: (x+2)(15x+1) = Final answer.
*August 10, 2014*

**physics**

a = (V-Vo)/t = (-4.4-6)/0.04=-260 m/s^2.
*August 10, 2014*

**physics**

I=(V1-V2)/(R1+R2) = (12-8)/(15+1)=
*August 10, 2014*

**PHYSICS**

d = 0.5a*t^2 = 10 m. 0.5a*(5.5)^2 = 10 15.125a = 10 a = 0.661 m/s^2. V = a*t = 0.661 * 5.5 = 3.636 m/s. d = Vo*t - o.5a*t^2 d=3.636*5.10 - 0.5*0.661*5.10^2=9.95 m.
*August 10, 2014*

**physics**

h = (V^2-Vo^2)/2g h = (0-(10^2)/-20 = 5.0 m.
*August 10, 2014*

**Alegbra**

a. (42,900-5100)/60 = b. Po = 42900 - 5100 = $37,800. P = Po*r*t/(1-(1+r)^-t) r = (2.5%/12)/100* = 0.00208 = Monthly % rate expressed as a decimal. t = 60 Months. P = (37,800*0.00208*60)/(1-1.00208^-60) = $40,251.02 Monthly Payments = P/t
*August 10, 2014*

**physics**

Vo = a*t = 17m/s^2 * 20s = 340 m/s. h1 = 0.5a*t^2 = 0.5*17*20^2 = 3400 m. = Ht. at which the engine shuts off. hmax = h1 + (V^2-Vo^2)/2g. hnax = 3400 + (0-(340^2)/-19.6 =9298 m. = 9.298 km above gnd. The rocket did not reach the required 12 km.
*August 9, 2014*

**physics**

T = 7days/week * 24h/day = 168 h. 0.2kW * 168h = 33.6 kWh Used. Cost = $0.14/kWh * 33.6kWh = $4.70
*August 9, 2014*

**physics**

D = Vo*t + 0.5a*t^2 D = 2*10 + 0.5*0.2*10^2 = 30 m.
*August 9, 2014*

**math**

B = # of boys in camp. 0.3B = # of boys from N.Y.S. 0.2 * 0.3B = 0.06B=# of boys from N.Y.C. (0.06B/B)*100% = 6% = Percentage of boys in camp from N.Y.C.
*August 8, 2014*

**math**

A = C pi*r^2 = pi*D pi*r^2 = pi*2r Divide both sides by pi*r r = 2 Inches. D = 2r = 2 * 2 = 4 Inches.
*August 8, 2014*

**Physics**

a. h = 12*s1n30 = 6 m. V^2 = Vo + 2g*h = 0 + 19.6*6 = 117.6 V = 10.84 m/s. b. m*g=83kg * 9.8N/kg = 813.4 N.=Wt. of the child. Fn = mg*cos30 = 813.4*cos30 = 704.4 N. = Normal = Force perpendicular to the slide. Fk = u*Fn = 0.30 * 704.4 = 211.3 N. = Force of kinetic friction. ...
*August 8, 2014*

**Physics**

d2 = d1+29 Vo2*t + 0.5a*t^2 = Vo1*t + 29 m 42t + 1.5t^2 = 28t + 29 1.5t^2 + 42t - 28t = 29 1,5t^2 + 14t = 29 1.5t^2 + 14t - 29 = 0 Use Quadratic Formula and get: t = 1.745 s. To pass the train. V = Vo + a*t = 42 + 3*1.745 = 47.24 m/s.
*August 8, 2014*

**Math 221**

See previous post: Thu, 8-7-14, 11:29PM.
*August 8, 2014*

**Math 221**

AC Method: 1. 2a^2 * 3a + 1 A*C = 2*1 = 2. 2+1 = 3 = B 2a^2 + (2a+a) + 1 Form 2 Binomials and factor: (2a^2+2a) + (a+1) 2a(a+1) + (a+1) (a+1)(2a+1). 2. 15x^2 + 31x + 2 A*C = 15*2 = 30 = 30*1. Sum = (30+1)=B. 15x^2 + (30x+x) + 2 (15x^2+30x) + (x+2) 15x(x+2) + (x+2) (x+2)(15x+1...
*August 7, 2014*

**algebra**

b = p-a-c
*August 7, 2014*

**math**

Shortest side = X. Other side = 2X. x + 2x > 11 3x > 11 X > 11/3 X > 3 2/3 X = 4 = Shortest possible length. 2X > 22/3 2X > 7 1/3 2X = 8.
*August 7, 2014*

**math**

Y yards * (3/8)jumps/yard = 3Y/8 Jumps.
*August 7, 2014*

**Physics**

Average Speed = (40+60)/2 = 50 km/h
*August 7, 2014*

**trigonometry**

X = 4 Ft/s Y = -2km/h = -2000m/3600s * 3.3Ft/m = -1.833 Ft/s Tan A = Y/X = -1.833/4 = -0.45825 A = -24.62o = 24.62o South of East. = 65.38o East of South = Direction. Magnitude = X/Cos A = 4/Cos(-24.62) = 4.4 Ft/s.
*August 7, 2014*

**trigonometry**

m*g = 200,000N. Fp = mg*sin A = 200,000*sin28 = 98,894 N = Force parallel with the incline = The pull on the rope.
*August 7, 2014*

**Physics**

Circumference=pi * 2r = 3.14 * 3=9.42 m. d = 0.5a*t^2 = 9.42 0.5*2.3*t^2 = 9.42 1.15t^2 = 9.42 t^2 = 8.19 t = 2.86 s.
*August 6, 2014*

**math**

3. Discount=((10.80-9.18)/10.80)*100%=15%. 4. Tax = (3.20/100)*Va = $1952 Solve for Va(assessed value). 7. Loan Amount = 7250-3000 = $4250 Cost = 7250 + 4250*(0.125/12)*9 = 8. Same procedure as #3. 9. Rate = ((4250-3910)/4250)*100% =
*August 6, 2014*

**algebra**

post it.
*August 4, 2014*

**Physics**

The horizontal component does not change
*August 3, 2014*

**Math**

h = 164t - 16t^2 = 400 Ft. -16t^2 + 164t = 400 -16t^2 + 164 - 400 = 0 Use Quadratic Formula and get: t = 4, and 6.25 seconds. Answer = 4 s. The rocket is falling when t = 6.25 s.
*August 2, 2014*

**physics**

10^-7J = 1 erg Multiply both sides by 10^7: 10^0J = 10^7 erg 1 J. = 10^7 erg.
*August 1, 2014*

**science**

Fr = 20N[270o] + 40N[45o] + 10[0o] = -20i + 40*cs45) + i40*sin45) + 10 = -20i + 28.28 + 28.28i + 10=38.28 + 8.28i Fr^2 = 38.28^2 + 8.28^2 = 1533.9 Fr = 39 N.
*July 31, 2014*

**physics**

a = (V-Vo)/t = (21.5-12.7)/3.45 =
*July 31, 2014*

**PHYSICS**

V = 300rev/min * 6.28rad/rev * 1min/60s = 31.4 rad/s. Circumference = pi*2r = 3.14 * 10=31.4 m. V = 300rev/min * 31.4m/rev * 1min/60s = 157 m/s. = Linear speed.
*July 30, 2014*

**physics**

F = m*a a = F/m = 3.0*10^4/0.06 = 5*10^5 m/s^2. a = (V-Vo)/t = 5*10^5 m/s^2 (75-0)/t = 5*10^5 5*10^5t = 75 t = 1.5*10^-4 s.
*July 30, 2014*

**physics**

m*g = 50kg * 9.8N./kg = 490 N. = Wt. of the box. Fp = 490*sin30 = 245 N. = Force parallel to the incine. Fn = 490*cos30 = 424.4 N. = Force perpendicular to the incline. Fk = u*Fn = 0.1 * 424.4 = 42.44 N. = Force of kinetic friction. At bottom of incline: KE + PE = mg*h - Fk*L ...
*July 30, 2014*

**Physics**

h = 32 m. A = 24.25o B = 18.2o Tan24.25 = h/X1 = 32/X1 X1*Tan24.25 = 32 X1 = 32/Tan24.25 = 71 m.=Hor. distance between boat A and the cliff. Tan18.2 = h/(X1+X2) = 32/(71+X2) (71+X2)*Tan18.2 = 32 71+X2 = 32/Tan18.2 = 97.33 X2 = 97.33-71 = 26.3 m=Distance between boat A and B.
*July 30, 2014*

**Physics**

m*g = 68kg * 9.8N./kg = 666.4 N. = Wt. of skier. Fp = 666.4*sin32 = 353.1 N. = Force parallel with incline. Fn = 666.4*cos32 = 565.1 N. = Normal = Force perpendicular to the incline. Fk = u*Fn = 0.05 * 565.1 = 28.26 N. = Force of kinetic friction. Fp-Fk = m*a a=(Fp-Fk)/m =(353...
*July 30, 2014*

**math**

12x = 3x+150 + 300 12x - 3x = 450 9x = 450 X = 50 Shirts.
*July 29, 2014*

**physics**

a = (V^2-(Vo^2))/2d =(0-(22^2))/8 = -60.5m/s^2. a = (V-Vo)/t t = (V-Vo)/a = (0-22)/-60.5 = 0.364 s.
*July 29, 2014*

**Physics**

The resistance of the voltmeter should be large compared to the resistance across which the voltage is being measured. If not, the voltmeter will act as an addition load on the circuit resulting in a lower reading. The voltmeter should be connected in parallel with the ...
*July 29, 2014*

**electric circuit**

Fuses are always connected in series with the circuit. Therefore, its' resistance should be small compared to the resistance of the circuit. The circuit of an Ammeter has a much lower resistance than a Voltmeter. So the fuse in the Ammeter has a higher current rating. ...
*July 29, 2014*

**physics**

1. 60s. * 1Wave/0.27s. = 222 Waves.
*July 28, 2014*

**PHYSICS**

V = Vo + a*t = 4.50 m/s. Vo + (-2.7)*3 = 4.5 Vo = 4.5 + 8.1 = 12.6 m/s. D = Vo*t + 0.5a*t^2 D = 12.6*3 - 0.5*2.7*3^2 = 25.7 m.
*July 28, 2014*

**Physics 2**

1. The step-down transformer reduces the primary voltage by a factor equal to the turns ratio. For instance, if the turns ratio was 4:1, the voltage across the secondary would be 1/4 of the primary voltage. In a step-up transformer with a turns-ratio of 1:4, the voltage across...
*July 28, 2014*

**physics**

d1 = d2 + 100m. 60t = 40t + 100 60t-40t = 100 20t = 100 t = 5 Hours.
*July 27, 2014*

**math**

Y > 8-5 Y > 3
*July 27, 2014*

**finance**

Program A: (5000/100,000)*100 = 5%Profit. Program B: (10,000/220,000)*100 = 4.55% Profit.
*July 27, 2014*

**Physics 2**

L = 1 mm to 1m. L = V/F F = V/L = 3*10^8/1*10^-3m = 3*10^11 Hz. F = 3*10^8/1m = 3*10^8 Hz.
*July 27, 2014*

**Physics 2**

L = V/F F = V/L = 300*10^6/300 = 10^6 Hz = 1 mHz
*July 27, 2014*

**physics**

A. Np/Ns = Vp/Vs = 120/12 = 10/1. Turns Ratio = 10:1 Ts = Tp/10 To find the number of turns on the secondary(Ts), we need to know the number of turns on the primary(Tp). B. 120 * I = 6 W. Solve for I. Fr = 1/(2pi*Sqrt(LC) Fr = 1(6.28*Sqrt( 0.40*30*10^-9) = 8.33 Million Hertz...
*July 27, 2014*

**science**

d = (V^2-Vo^2)/2a=(0-(20^2)/-8.6=46.51 m = Stopping distance. d = 55+22+5 = 82 m. = Distance through intersection. d = Vo*t + 0.5a*t^2 = 20*(3-0.25) + 0.5*2*(3-0.25)^2=62.6 m. Therefore, the driver must step on the brakes; because he or she cannot drive the required 82 meters ...
*July 27, 2014*

**physics**

Wt. of Cart=m*g = 250kg * 9.8N/kg=2450 N Fp = 2450*sin50 = 1877 N. = Force Parallel to the incline. Fn = 2450*cos50 = 1575 N. = Normal force Fk = u*Fn = 0.22 * 1575 = 346.5 N. = Force of kinetic friction. Fe-Fp-Fk = m*a Fe-1877-346.5 = m*0 = 0 Fe-2223 = 0 Fe = 2223 N. = Force ...
*July 27, 2014*

**trigonometry**

Smaller Pulley: V=15rev/12s * 6.28rad/rev = 7.85 rad/s Larger Pulley: V = (6cm/20cm) * 7.85 = 2.36 rad/s.
*July 26, 2014*

**physic**

da = 0.5g*t^2 = 4.9*2^2=19.6 m. in 2 s. Va = Vo + g*t = 0 + 9.8*2 = 19.6 m/s in 2 s. Da = Db - 19.6 19.6t + 4.9t^2 = 30t + 4.9t^2 - 19.6 19.6t - 30t + 4.9t^2 - 4.9t^2 = -19.6 -10.4t = -19.6 t = 1.88 s. to reach gnd. h = 30t + 4.9t^2 = 30*1.88 + 4.9*1.88^2 = 73.9 m.
*July 25, 2014*

**PHYSICS**

Circumference=pi*2r = 3.14 * 20=62.83 m. d = (270o/360o) * 62.83m = 47.12 m. = Distance traveled. d = r*t = 47.12 m. r = 47.12/t = 47.12/20 = 2.36 m/s=Speed. Displacement = 10m[270] - 10[0o] -10 - 10i = -14.14m.[45o] = 14.14m[-45o]
*July 23, 2014*

**Math**

1344 = 1*1344 = 1*2*672 = 1*2*3*224 = 1*2*3*4*56 = 1*2*3*4*7*8. 1440 = 1*1440 = 1*2*720 = 1*2*3*240 = 1*2*3*4*60 = 1*2*3*4*5*12=1*2*3*4*5*6*2 2160 = 1*2160 = 1*2*1080 = 1*2*3*360 = 1*2*3*4*90 = 1*2*3*4*5*18=1*2*3*4*5*6*3 GCF = 4. 2. Income = $X. (1/10+1/3+1/5)X + 1320 = X (3/...
*July 22, 2014*

**Math**

1. 40%/100% = 40/100 = 2/5. 2. The largest side should be less than the sum of the two smaller sides: 9cm, 16cm, and 8cm. 16 < 9 + 8.
*July 22, 2014*

**algebra**

6x - (2/5) 6*0 - (2/5) = -2/5 6*1 - (2/5)=6/1 - 2/5 = 30/5 - 2/5=28/5. 6*2 - 2/5 = 12/1 - 2/5 = 60/5 - 2/5=58/5 (6x-2)/5 (6*0-2)/5 = -2/5 (6*1-2)/5 = 4/5 (6*2-2)/5 = 10/5 = 2.
*July 22, 2014*

**Math**

D. A,C,B,D.
*July 22, 2014*

**Math 221**

2 < Y <= 7.
*July 20, 2014*

**mat/117**

F(x) = -3x^2 + 3x + 9 = 0 Divide by -3: x^2 - x - 3 = 0 Use Quadratic Formula and get: X = 2.30, and -1.30 = Approx. 2, and 3.
*July 20, 2014*

**physics**

3[90o] + (-4) + F = 0 3i + (-4) + F = 0 F = 4 - 3i = 5N[-37o] = 5N[37o] S. of E. =5N[53o] E. of S.
*July 20, 2014*

**math**

X oz. of black beans. (X+180) oz. of red beans. Total = X + (X+180) = 2x + 180. X/(2x+180) = 0.20 x = 0.4x + 36 0.6x = 36 X = 60 Oz. of Black beans. X+180 = 60+180 = 240 Oz. of red beans. Total = 60 + 240 = 300 oz. of beans. 0.3 * 300 = 90 oz. of mixed beans.
*July 17, 2014*

**math**

We need the height. A = 2*W*h + 2*L*h A = 2*6*h + 2*9*h
*July 16, 2014*

**math**

A = 2.60*r^2 = 2.60 * 5^2 = 65 Ft.^2
*July 16, 2014*

**trig**

X = 60 Ft. = Run Y = Rise A = 21o Tan 21 = Y/X = Y/60 Y = 60*Tan 21 = 23.0 Ft. = Rise
*July 16, 2014*

**physics**

Ma*V = 1500*25 = 37,500 = Momentum of Boxcar A. (Ma+Mb)*V = 37,500 (1500+2000)V = 37,500 3500V = 37,500 V = 10.71 m/s.
*July 14, 2014*

**physics**

r = 60km/h = 60,000m/3600s. = 16.67 m/s. d = d1 + d2 d1 = r*t = 16.67m/s * 1s = 16.7 m. d2 = (V^2-Vo^2)/2a d2 = (0-(16.7)^2/-6 = 46.3 m. d = 16.7 + 46.3 = 63.0 m.
*July 12, 2014*

**electric circuit**

We can build 3 12V batteries: 36/12 = 3. We can connect them in parallel to make a 12V-4.5A battery: I = 3 * 1.5 = 4.5A. P = V*I = 12 * 4.5 = 54 Watts.
*July 12, 2014*

**finance**

Amount = -12-145+3.50+80 = -$73.50
*July 11, 2014*

**PHYSICS**

The given numbers doesn't make sense; please double check the numbers and show all units.
*July 11, 2014*

**PHYSICS**

m*g = 2kg * 9.8N/kg = 19.6 N. = Wt. of object being pushed. Fp = 19.6*sin50 = 15.0 N. = Force parallel to the incline. Fn = 19.6*cos50 = 12.6 N. = Normal = Force perpendicular to the incline. Fk = u*Fn = 0.40 * 12.6 = 5.0 N. = Force of kinetic friction. a=(Fap-Fp-Fk)/m = (50-...
*July 11, 2014*

**environmental engineering**

120Lbs/h * 454g/Lb. * 1h/3600s=15.13 g/s of flyash. 25Ft^3/s * 1m^3/35.94Ft^3 = 0.696 m^3/s. Concentration = 15.13g/s * 1s/0.696m^3 = 27.75 g/m^3 = 2.775*10^6 ug/m^3.
*July 10, 2014*

**environmental engineering**

a. 0.05mg/L * 8L = 0.40 mg. b. Yes, there are 0.05mg/L.
*July 10, 2014*

**Physics**

Same direction: I = I1 + I2. Opposite direction: I = I1 - I2.
*July 9, 2014*

**physics**

a=F/m = N[90o]/220 = 0.00455N[90o] m/s^2
*July 9, 2014*

**physics**

Reading=mg*sin A = 980*sin32.7 = 529 N. = Wt. parallel to the incline.
*July 9, 2014*

**Physics**

h = L*sin A = 8.33*sin 24.5 = 3.45 m. V^2 = Vo^2 + 2g*h V^2 = 4.12^2 + 19.6*3.45 = Solve for V.
*July 8, 2014*

**Physics**

u = 75/400 = 0.1875
*July 8, 2014*

**Physics**

d = 300 m = 0.3km t = 15 min. = 0.25 h. a. V = d/t = 0.3km/0.25h = 1.2 km/h c. Tan A = 4/1.2 = 3.333 A = 73.3o West of North due to wind. Heading = 73.3o East of North = 16.7o CCW. Vw + Vs = 1.2i -4 + Vs = 1.2i Vs = 4 + 1.2i = 4.18km/h[16.7o] CCW = 4.18km/h[76.3o] East of North.
*July 8, 2014*

**mechanism physics**

(m1+m2)V = m1*V1 (10+5)V = 10*10 Solve for V.
*July 8, 2014*

**Math**

P = (Po*r*t)/(1-(1+r)^-t) 2. Po = $146,800 r = (5.25%/12)/100% = 0.004375 = Monthly % rate. t = 30yrs. * 12mo./yr. = 360 Months. Plug the above values into the given Eq and get: P = $291,828.61 Monthly Payment = P/t 4. Same procedure as #2. 6. I = P-Po 8. I = P-Po
*July 7, 2014*

**Physics**

Vo = 26m/s[60o] Yo = 26*sin60 = 22.5 m/s. a. Y = Yo + g*Tr = 0 @ max. ht. Tr = -Yo/g = -22.5/-9.8 = 2.30 s. = Rise time. b. h max = -(Yo^2)/2g = -(22.5)^2/-19.6 = 25.83 m. h = 0.5g*t^2 = 25.83/2 = 12.91 m. 4.9t^2 = 12.91 t^2 = 2.64 Tf = 1.62 = Fall time. Tr+Tf = 2.30 + 1.62 = ...
*July 7, 2014*

**Physics**

A. Momentum = m*V. Case A: Change = 0 - mV = -mV. Case B: Change = -mV - mV = -2mV. Answer: Case B. B. Case A: a1 = -mV/T. Case B: a2 = -2mV/T. a2/a1 = (-2mV/T)/-mV/T = 2 a2 = 2a1. Answer: Case B.
*July 7, 2014*

**Physics**

a. KE = 0.5m*V^2 KE = 0.5*11300*19.3^2 = 2,104,569 J. b. Momentum = 5 * m*V = m1*V1 5 * 11,300*V = 11,300*19.3 56,500V = 218,090 V = 3.86 m/s. KE = 0.5*5m*V^2 KE = 0.5*5*11,300*3.86^2 = 420,914 J.
*July 7, 2014*

Pages: <<Prev | 1 | 2 | 3 | 4 | **5** | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | Next>>