# Search results

1. ### Misc. Hydrostatics problem in a water vessel

I don't actually know what you mean by your last paragraph. How would you would the small bleed tube operate as a level sensor? Can you please explain how something like that might work?
2. ### Misc. Hydrostatics problem in a water vessel

Thanks for the advice. Your feedback was exactly what I was looking for.
3. ### Misc. Hydrostatics problem in a water vessel

I am trying to design a water vessel system that maintains it's water level as it is consumed. In item 1. It's a simple water barometer, where the height of water in the column can be supported by atmospheric pressure until 10.34. In item 2. There are two columns that are open to atmosphere...
4. ### Calculating Power at source from Intensity at distance R

Figured it out. (4 pi r^2)=P/I where r=46. P=4.2*10^-4
5. ### Calculating Power at source from Intensity at distance R

Homework Statement An enclosed chamber with sound absorbing walls has a 2.0 m × 1.0 m opening for an outside window. A loudspeaker is located outdoors, 46 m away and facing the window. The intensity level of the sound entering the window space from the loudspeaker is 42 dB. Assume the acoustic...
6. ### Richardson Extrapolation with 3 steps?

i think i got it. thank you very much zondrina!
7. ### Richardson Extrapolation with 3 steps?

Thank you! So you would run the central difference formula with 2, 1, 0.5. then for we would use f(2) and f(1) , and then again with f(1), f(0.5)? Maybe what confuses me is when they say "calculate the TRE of the last estimate", its just the second of two estimates calculated using Is it...
8. ### Richardson Extrapolation with 3 steps?

Homework Statement [/B] use richardson extrapolation to estimate the first derivative y=ln(x), x=5 using steps of 2, 1, 0.5. Four decimal points. obtain true relative error for the last estimate and comment on its value. Homework Equations [/B] deriv ln(x)=1/x The Attempt at a Solution I...
9. ### Differential Equations System Solutions

Thank you so much! That makes total sense!
10. ### Differential Equations System Solutions

Okay, I work this out to y_1=1/4 and y_2=1/2... which seems to fit in the equation... but I am still not really sure why the coefficients for the e^(-4t) don't seem to match the solution
11. ### Differential Equations System Solutions

I have not encountered this type of problem before. How do you go about finding the particular solution?
12. ### Differential Equations System Solutions

Homework Statement Consider the initial value problem for the system of first-order differential equations y_1' = -2y_2+1, y_1(0)=2 y_2' = -8y_1+2, y_2(0)=-1 If the matrix [ 0 -2 -8 0 ] has eigenvalues and eigenvectors L_1= -4 V_1= [ 1...
13. ### High order differential equations: undetermined coefficients

right... 3 roots... so r^3-r=0 r=0, r=1, and... r=-1 -1-(-1)=0 I always get stuck on the stupidest mistakes. I really appreciate it! thanks
14. ### High order differential equations: undetermined coefficients

Homework Statement If the method of undetermined coefficients is used to find a particular solution yp (t) to the differential equation y'''-y'=te^(-t)+2cos(t) should have the form: ? Homework Equations The Attempt at a Solution LHS r^3-r=0 roots= 0, 1 y_c(t)=c_1e^t RHS...
15. ### 2nd order differential equation: undetermined coefficients

Got it... I was making a mistake with my derivative... I feel stupid. Thanks Mark44!
16. ### 2nd order differential equation: undetermined coefficients

You add a coefficient t so the guess becomes At+B+Cte^(-t) right? When I plug that back in, it still cancels out
17. ### 2nd order differential equation: undetermined coefficients

Homework Statement y''-y=t-4e^(-t) Homework Equations method of undetermined coefficients The Attempt at a Solution solving for characteristic equation first y''-y=0 r^2-1=0 c_1e^(-t)+c_2e^(t) RHS particular solution t-4e^(-t) y_p(t)= At+B+Ce^(-t) y_pt'(t)=A-Ce^(-t)...
18. ### Conservation of Energy falling rod

Homework Statement A uniform ladder having mass 14kg and length 3m is released from rest when it is in the vertical position. If it is allowed to fall freely, determine the angle Theta at which the bottom end A starts to lift off the ground. For calculation assume the ladder is a slender rod...
19. ### Wind Turbine Question

Homework Statement During a sustained wind the blades on a two blade horizontal–axis wind turbine is turning with an angular velocity of 5 rad/s. If initially the blades have an angular velocity of 2 rad/s, determine the distance point P on the tip of the blade has traveled in 3.0 seconds...
20. ### Differential equations - backwards problem

Homework Statement If y=y(t) is the solution of the initial value problem { y'+(2t+1)y=2cos(t) y(0)=2 then y''(0)=? it is a multiple choice practice problem with choices y''(0)=2 y''(0)=-2 y''(0)=4 y''(0)=0 y''(0)=-4 Homework Equations The Attempt at a Solution Im really not sure how...
21. ### Differential Equations: Bernoulli Equation

i always feel so stupid when i come on the site. yes it is the reciprocal. thank you for your help
22. ### Differential Equations: Bernoulli Equation

Homework Statement Find the general solution: y'-3y=(y^2) Homework Equations The Attempt at a Solution divide both sides by y^2 y'(y^-2) -3(y^-1) = 1 we know v=y^(n-1) v=y^-1 v'=d/dx(y^-1) v'=-(y^-2) y' plug it back into y'(y^-2) -3(y^-1) = 1 -v'-3v=1 this is where I think I am...
23. ### Kinematics Question. Incline, Spring, Friction

sumF_y=0 N-mgcos30=0 N=17 N sumF_x=0 F_spring-F_friction=m_block*accel_block kx-uN=ma if static, accel=0 410(0.5)-u(17)=0 u=12.06 doesnt seem right... i think the x is wrong for the spring but i can't visualize it.
24. ### Kinematics Question. Incline, Spring, Friction

Homework Statement Practice problem for midterm. Homework Equations [/B] T_1+U_1=T_2+U_2 U_spring=1/2kx^2 The Attempt at a Solution [/B] Set X-axis along the 30 degree line and the Y-axis perpendicular. I'm not sure how to consider the friction constant into the formula. Any help is...
25. ### Finding the zeroes for cubic equation

Thanks for your help. Sure is frustrating when you start doubting yourself. Take care.
26. ### Finding the zeroes for cubic equation

(5i)^3+25(5i)= -125i+125i=0 (-5i)^3+25(-5i)= 125i-125i=0 0^3+25(0)=0 seems to check out for me. however this is not giving me the correct answer according to the solution
27. ### Finding the zeroes for cubic equation

Homework Statement Find all zeroes for the function f(x) f(x)=x^3+25x Homework Equations The Attempt at a Solution I tried factoring out x out of it. x(x^2+25) and again to give x[(x+5i)(x-5i)] this would give me the 0,-5i,+5i as the zeroes. Doesn't seem to be right though. Any...
28. ### Rotation matrix vs regular matrix

Can you calculate eigenvalues and eigenvectors for rotation matrices the same way you would for a regular matrix? If not, what has to be done differently?
29. ### Linear algebra matrices multiplication (transpose)

S0 + identity matrix on left side... = [-4 0] ... then /2= [-2 0] -8 -6 ......-4 -3 GOT IT!
30. ### Linear algebra matrices multiplication (transpose)

Homework Statement We are looking for the matrix A Homework Equations (A^transpose)^transpose=A The Attempt at a Solution i would start with finding the transpose of the matrix. -5 0 -8 -7
31. ### Single Photon/Indistinguishabiliity principle experiment

Thank you! So if the obstacle was taken away then 100% of the photons would end up being reflected-transmitted/transmitted-reflected and thus all ending up hitting the detector on the right. This is due to interference. Right?
32. ### Single Photon/Indistinguishabiliity principle experiment

If a single photon light source shoots a photon through the "attached" path. What is the percentage of the photon will make it to each detector. The light source is the box, the photon trajetory is yellow, beamsplitter is blue, mirror is black, detectors are purple, and obstacle is red. I think...