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  1. K

    Strain Gage Errors

    Homework Statement What are the potential errors in measuring strain with strain gages? How can these errors be minimized? The Attempt at a Solution In my class notes, I have the four Errors. 1-Gage mounting (glue thickness & flex) Use a thin layer of glue and make sure the layer is...
  2. K

    How many bits should be employed to obtain a resolution

    Homework Statement An A/D converter is to operate with a full-scale voltage of 10V. How many bits should be employed to obtain a resolution of 0.01%? Homework Equations Resolution = Full Scale voltage / (2N - 1) The Attempt at a Solution .01% * 10 V = .01/100 * 10 V = .001...
  3. K

    Statics homework problem

    Homework Statement http://img843.imageshack.us/img843/5370/helpxd.jpg [Broken] Homework Equations Sin law The Attempt at a Solution I got to: F1/sin(105) = F1u/sin(45) = F1v/sin(30) I get F1u = - 219 and F1v = 254.5.... It says it is wrong, not sure what I did.
  4. K

    Intergration my parts. Reduce.

    Homework Statement S P^4 e^-P DP Homework Equations My parts. The Attempt at a Solution I know you can do u = P^4, and DV = e^-P Then, you get du = 4P^3 dx and V = -e^-P -P^4 e^P + S 4P^3 e^-p dx Now, I can just repeat that for the intergral until I get to were the P...
  5. K

    Expanding the binomial

    Homework Statement by expanding the binomial show that ( (Sqtroot(3)/2) + (1/2)i )^4 = ( (-1/2) + (sqroot(3)/2)i ) The Attempt at a Solution I'm stuck, I now ( (Sqtroot(3)/2) + (1/2)i )^4 = ( (9/16) + (1/16)i ) But that's all I got, don't know the next steps.
  6. K

    Gaussian Elimination Matrix

    Homework Statement Using Gaussian Elimination: 3x - 2 y = 5 6x-4y =7 The Attempt at a Solution [ 3 -2 5] [6 -4 7] * top row by 1/3 [1 -2/3 5/3] * Top row by -6, add to bottom row: [0 0 -3] So I get this: [1 -2/3 5/3] [0 0 -3] How can 0y equal -3?
  7. K

    Convert the equation to a first order system.

    Homework Statement Convert the equation to a first order system. d^2y/dt^2 + 3dy/dt + 2y = 0 The Attempt at a Solution Set d^2y/dt^2 = dv/dt dy/dt = V So, I now have: dv/dt + 3v + 2y = 0 Now, i'm not sure what to do with that Y, In my notes we only did examples with...
  8. K

    Find all Equilibrium points for the following systems.

    Homework Statement Find all Equilibrium points for the following systems. B. dx/dt = 5x - x^2 - 3xy dy/dt = 8y - 3xy - 3y^2 The Attempt at a Solution 0 = x(x + 3y - 5) 0 = y(y + x - 8/3) Equilibrium points: (0,0) but I can't find anymore? is (0,0) the only one?
  9. K

    How to maximize a function?

    Homework Statement http://img262.imageshack.us/img262/678/im000724.jpg [Broken] Uploaded with ImageShack.us The Attempt at a Solution http://img843.imageshack.us/img843/5651/im000726.jpg [Broken] Uploaded with ImageShack.us I got all the way to g, but I don't know how to...
  10. K

    Intergrating Factor - dy/dt = -2ty + 4e^-t^2

    Homework Statement Solve the differential equations [Find the general solution y(t)=KYh(t) + Yp (t)]. Use the method of finding the integrating factor. dy/dt = -2ty + 4e^-t^2 The Attempt at a Solution S = intergrat dy/dt = -2ty + 4e^-t^2 dy/dt + 2ty = 4e^-t^2 P(t) = 2t b(t)...
  11. K

    Dy/dt = sin^2 y ebilibrium

    Homework Statement I need to find the equilibrium solutions dy/dt = sin^2 y The Attempt at a Solution I don't know what to do with the sin^2. If it was just sin, it would be easy, 0, pi, -pi, 2pi, -2pi.....etc...... But it's not, I have a Ti-84 plus calculator. So, i don't...
  12. K

    Euler's Method - dy/dt = y^2-4t

    Homework Statement dy/dt = y^2-4t - y(0) = 0.5 - 0 <_ t <_ 3.0 - Change in t = 0.5 I have to use Euler's method to make a table, but I'm not sure how to handle the t. I have only done it with y's and no other variables.
  13. K

    Dp/dt = 4p-3p^2-p^3Diff. Equation.

    Can someone tell me were I went wrong. This just doesn't seem right. If some how it is, I need help with the next part. Not sure how. Talking about problem #2. http://img513.imageshack.us/img513/8535/part1mc.jpg [Broken] Uploaded with ImageShack.us...
  14. K

    Task of building a water barometer.

    Homework Statement Your physics teacher has assigned you the task of building a water barometer. You've learned that the pressure of the atmosphere can vary by much as 5 percent from 1 standard atmosphere as the weather changes. A. What is the minimum height you must build your barometer...
  15. K

    D.E.Q. Find the equilibrium and general solutions

    Homework Statement Find the equilibrium and general solutions dp/dt = 4P - 3P^2 - P^3 The Attempt at a Solution Equilibrium: dp/dt = -P(P^2 - 3P - 4) dp/dt = -P(P+4)(P-1) Equilibrium solutions: P = 0, P = 1, P= -4 General solutions: 1/(4P-3P^2 - P^3) dp = 1dt This is...
  16. K

    202,000=32,800e^k*20 - Solve for K

    Homework Statement Did most the problem, but know I'm stuck here: 202,000=32,800e^k*20 I need to solve for K The Attempt at a Solution Log 202,000 = k*20 log 32,000 e Do you move the e out in front too? I'm not sure, anyway, I'm stuck here. Not sure what to do or even if you use...
  17. K

    Line Integral Fundamental Theorem

    Homework Statement Use Your Phi(from part 1) and the fundamental theorem of line integrals to evaluate the same line integral. (should get the same answer!) The Attempt at a Solution Phi from part 1: Phi = xy+ y^2 +C The line from before go from (0,2) to (-2,0) r(a) = (0,2)...
  18. K

    Line Integral

    Homework Statement F= <y, x+2y> Show F is conservative and determine potential function.(Determine Phi so that gradient phi = F) The Attempt at a Solution F= <y, x+2y> = <phi-x, phi-y> Phi-x = y-------------> Phi = yx + Cy------Part respect to Y----> = (Y^2/2)X I'm not sure...
  19. K

    Volume of Solid

    Homework Statement The volume of the solid below the plane: z=2x and above the paraboloid z=x^2 + y^2. I need help setting this one up, I can handle the evaluating. The Attempt at a Solution I just don't know.
  20. K

    Quick Question.

    Homework Statement T(x, y, z) = 200e^(−x^2−3y^2−9z^2 ) I'm not sure how to get the derivative in terms of x,y or z. The Attempt at a Solution For x: -200x^2e^(−x^2−3y^2−9z^2 )(-2x)????? Is this right? Probably not, how do i do it?
  21. K

    Triple integrals

    Homework Statement Volume between Y=1-X and Y = Z^2 -1 The Attempt at a Solution http://img254.imageshack.us/img254/1743/42932830.jpg [Broken] Uploaded with ImageShack.us Sorry, not a good drawer. 0 < y < 1 0< x < SqRoot: 1-y -1 < y < 0 0 < Z < Sqroot: 1 + y I'm not...
  22. K

    Ballistic Spring System.

    Homework Statement You have been ask to design a "ballistic spring system" to measure the speed of bullets. A bullet has a mass of m is fired into a block with mass M. The block, with the embedded bullet, then slides across a frictionless table and collides with a horizontal spring whose...
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