# Recent content by killersanta

1. ### 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. ### How many bits should be employed to obtain a resolution

Wow, thank for the quick reply. I know that, but don't you times it by 10 V? Isn't the units for resolution volts? I assumed when they said "resolution of 0.01%," I assumed this was .01% of the full scale voltage. Is that wrong to assume? Should resolution just equal .0001? Then N= 16.6 = 17...
3. ### 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...
4. ### 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.
5. ### 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...
6. ### 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.
7. ### Convert the equation to a first order system.

What reply box? ______________________________________ Now, I'm having troubles again. dv/dt = -3v -2y dy/dt=v A = [-3 -2 ] [1 0] Det: [-3-Lamba -2 ] = 0 [1 0-lamba ] (-3 - lamba)(0-lamba) -(-2)(1) = 0 Lamba2 -3 lamba + 2 =0 (lamba...
8. ### 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?
9. ### 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...

Thank you.
11. ### 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?
12. ### How to maximize a function?

Yeah, I caught that. Thank you though.
13. ### How to maximize a function?

Nevermind, I got it....56.25lbs...
14. ### How to maximize a function?

I think I set y(t) to 0. If this is the case, I get: 0 = -100e^(-1/20t) + 150e^(-1/40t) How do I get rid of the e's? I'm not sure how with the numbers is front. Without the numbers in front I know I could rise them to ln.
15. ### 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...