Recent content by winbacker

1. Easy Laplace Transform help!

"easy" Laplace Transform...help! Homework Statement Evaluate L{(e^-2t)*t*sinht} Homework Equations translation theorem The Attempt at a Solution Just to clarify: the contents of the bracket is the product of 3 terms: e^-2t (e to the power of -2t) t sinht all...
2. AAaaaargh! I don't understand Aarggghh!

I think i see what you're saying PhanthomJay but why then did he orient the triangle at D differently than the other triangle? If the reaction at D was parallel to the other 2 forces, shouldnt both triangles be oriented the same way? So that their hypotenuses are parallel??
3. AAaaaargh! I don't understand Aarggghh!

AAaaaargh! I don't understand!! Aarggghh! Homework Statement OK so I'm trying to understand the solution to a mechanics of materials problem that I'm working on. I understand the entire solution EXCEPT for 3 very tiny and BASIC lines of math which draw upon some BASIC trig property of which...
4. Easy ellipse question

well, I assume the center of the ellipse is at (-1,0). Otherwise I am stumped....how do they get 2cost?? And how is y = sint? I am very confused...
5. Easy ellipse question

I have the solution to a problem and I need help understanding how the solution was obtained. I have to take an equation of an ellipse and transfer it to parametric form. The ellipse has the equation: (x+1)^2 + 4y^2 = 4. The solution has the ellipse parameterized as follows: x+1 =...
6. Double integral in polar form: how do you find the boundaries?

Ok, well I know that once theta = 2pi, the behavior of of sinQ will repeat itself. Should I then plug in 2pi to the equation and work with that? I know the value of sinQ becomes zero again at pi. Does this mean the outer boundary is from 0 to pi?
7. Double integral in polar form: how do you find the boundaries?

Hi I need to use a double integral to find the area of the region bounded by: r = 3 + 3sinQ where Q = theta. I know the bounds of the inner integral are from 0 to 3 + 3sinQ. However, I do not know how to determine the bounds of the outer integral. Any help would be greatly appreciated.
8. The boundaries of doule integrals in polar form

Hi I need to use a double integral to find the area of the region bounded by: r = 3 + 3sinQ where Q = theta. I know the bounds of the inner integral are from 0 to 3 + 3sinQ. However, I do not know how to determine the bounds of the outer integral. Any help would be greatly appreciated.
9. Integral involving square root -need help

the first one
10. Integral involving square root -need help

Homework Statement integrate sqrt(1-x^-2/3)^1/2. Homework Equations The Attempt at a Solution The only thing I can think of is u substitution with u = 1 - x^-2/3. Obviously this cannot work because du differs by more than just a constant. I guess I need to somehow factor...
11. Can someone define a line integral?

I have just begun exploring the topic of line integrals for my Calculus 3 class. Although I can perform the calculation properly, I don't understand the physical significance of what I've just calculated. For example, I know that when I calculate the integral of a function which is defined...
12. The current and magnetic field of an ideal solenoid.

This is not a homework question, it's just to help my conceptual understanding of two quick things: Suppose you have an ideal solenoid placed horizontally in front of you. The current is traveling (spiralling) from your left to your right. What direction is the magnetic field inside the...
13. Acceleration in terms of velocity and radius?

Acceleration in terms of velocity and radius??! Homework Statement Which one of the quantities below has dimensions = [(ML)/(T^2)] MV MV^2 (MV^2)/R MRV (MV^2)/(R^2) Homework Equations My physics textbook defines 3 basic dimesions: M = Mass. T = Time. L = Length...