Recent content by twiztidmxcn

Homework Statement Let B be 4x4 matrix: [ 1 3 -2 2 ] [ 0 1 1 -5 ] [ 1 2 -3 7 ] [ -2 -8 2 -1 ] a) Do the columns of B span R^4? b) Does the equation Bx = y have a solution for each y in R^4? Sorry for the crappy matrix, its a 4x4, R^4 is the funky double R for 'Reals'...

Homework Statement What is the Laplace transform of f(t) = t^2 - 18 for 0 < t < 3 and f(t) = (t-3)^2 for t>3?Homework Equations Laplace Transforms 3. Work Using Heaviside/step function, made equation into: f(t) = t^2 - 18 + u(t-3)( (t-3)^2 - (t^2-18) ) Then, using Laplace transforms...

Homework Statement Consider y''(t)+(k/m)*y = 0 for simple harmonic oscillation A) Under what conditions on Beta is y(t)=cos(Beta*t) a solution? B) What is the period of this solution? C) Sketch the solution curve in the yv-plane associated with this solution (Hint: y^2 + (v/Beta)^2)...

Haha, I just caught my error. Ima give it a whirl now with the CORRECT integral, hehe. Thank you nrged *edit* - got it, much thanks to you nrged

hrm, I've re-done the integration multiple times and keep getting the same thing. I am integrating this: (x*e^(-3t))' = C*e^(-4t) After integrating I get: x*e^(-3t) = ( -C / [3e^(3t)] ) + C Divide out the u(t) = e^(-3t) and end up with this: x = (-C / 3) + C*e^(3t) I've also done this...

Solve: dx / dt = 3*x + y dy / dt = -y As for solving this, here is what I've got so far: Since dy/dt is separable, I found that dy / y = -dt, integrated, and solved explicitly for y: y = Ce^-t I then plugged Ce^-t for y in the dx / dt portion of the system and found that...

This question is an initial value problem for diffeq. We are asked to solve explicitly for y. (1+cos(x))dy = ((e^(-y))+1)*sin(x)dx , y(0) = 0 I attempted a separation of variables and ended up with the following: dy / ((e^(-y))+1) = (sin(x) / (1 + cos(x))) dx I know that my...

Woah...I'll take a look at it and get back if I need any more help

Homework Statement So my question is as follows: Find the volume of the solid bounded by z = 3x^2 + 3y^2 and z = 6sqrt(x^2 + y^2) The Attempt at a Solution I drew the graphs of these out, with the z = 3x^2 + 3y^2 being a circular paraboloid w/ vertex at (0,0,0) and extending in...

I have this problem as a homework question for my MEB/Thermodynamics class and have been having some trouble with it. A 10.0 m^3 tank contains steam at 275°C and 15.0 bar. The tank and its contents are cooled until the pressure drops to 1.2 bar. Some of the steam condenses in the process...

thx for the help turns out i had most of what i needed, but had a couple numbers switched around and for some reason was just using systems of equations rather than doing actual math and not being a dumb ass

thx to you both, ended up getting it dV = k*dq / r, integrate both sides, end up with V = Q/4*pi*epislon naught * r, which is what i needed

These circuit questions seem to give me so many problems, this question in particular. What are the emf and internal resistance of the battery in the figure below? I have the answers, that emf is 9V and internal resistance is 0.5 ohms, however I'm having problems getting there. What...

Doin a question based around RC circuits and was in a bit of a bind, lookin for some help. The capacitor in the figure below begins to charge after the switch closes at t = 0s. a) what is deltaVc when t >> 0 after switch is closed? b) what is Qmax in terms of emf, R and C? c) in this...

About a month ago I asked what could be the part 1 of this question, and here's the part two. Say you take a thin flexible rod with charge Q, bend it into a semicircle (half circle going from pi/2 to 3pi/2) with radius R. Find an expression for the electric potential at the center of that...