# Search results

1. ### Streamlines from strain rate tensor

I was reading about strain rate tensors and other kinematic properties of fluids that can be obtained if we know the velocity field V = (u, v, w). It got me wondering if I can sketch streamlines if I have the strain rate tensor with me to start with. Let's say I have the strain rate tensor...
2. ### A Convolution, singularity, kernel, principle values, linear stability analysis, quadrature points

Thanks a lot for the information, fresh_42. I'll try to look up lecture notes that are made available online. I think that's the easier way to learn too.
3. ### A Convolution, singularity, kernel, principle values, linear stability analysis, quadrature points

Yes, I agree it's a rather broad question. Sorry about that. I would actually like to learn about singularities in a strict mathematical sense. So, if I have to learn about convolution, singularity and kernels in particular where should I start looking? I did google about them a bit, found some...
4. ### A Convolution, singularity, kernel, principle values, linear stability analysis, quadrature points

I'm reading a book on vortex methods and I came across the above mentioned terms, however, I don't understand what they mean in mathematical terms. The book seems to be quite valuable with its content and therefore I would like to understand what the author is trying to say using the above...
5. ### I Express x in terms of the constants

I have the expression, A(Bx + 1) = C*d^(2x) where A,B,C and d are constants. How to arrive at an expression for x in terms of A,B,C and d? I have tried doing this: Log [A(Bx + 1)/C] = Log [d^(2x)] 2xLog(d) = Log[A(Bx + 1)/C] but I'm unable to arrive at an explicit expression of x in terms...
6. ### I Order of derivatives

If v is of order δ, what is the order of ∂v/∂x and ∂2v/∂x2 ?
7. ### What does this mean? (equation for viscous flows)

While reading a text book on viscous flows, I came across the following interpretation of an equation: where, v is the vertical component of the free stream velocity and y is the vertical distance from the surface of a solid and Re is the reynolds number. Can someone please help me...
8. ### The Determinant

What is the main idea behind the determinant? What was the main purpose for which it was conceived?
9. ### Tangent vector

But the rate of change at a point can never be a tangent at that point. It has to be integrated to obtain the equation of the tangent.
10. ### Tangent vector

Then why is the rate of change called the tangent vector itself?
11. ### Tangent vector

I was reading about the tangent vector at a point on a curve. It is formulated as r' = Lim Δt→0 [r(t+Δt) - r(t)] / Δt (sorry for the misrepresentation of the 'Lim Δt→0 ') where r(t) is a position vector to the curve and t is a parameter and r' is the derivative of r(t). All I can...
12. ### Straight line in a plane

Post #2 helped me understand the negative reciprocal rule for perpendicularity. Post #11 helped me understand the negative reciprocal rule for perpendicularity being applicable, in context of post #10, only after A.B=0 being valid. The combination of both posts helped me understand everything...
13. ### Straight line in a plane

Thank you RyanH42.
14. ### Straight line in a plane

How is it right to say that A is perpendicular to ax+by=0 just because A is perpendicular to B?
15. ### Straight line in a plane

I think the above quoted message is misleading here. My question would have been as follows: Is it OK to say that A is perpendicular to ax+by=0 because A is perpendicular to B?

17. ### Straight line in a plane

Is it OK to say that A is perpendicular to ax+by=0 because A.B=0? Another statement from the same book conveying this meaning.
18. ### Straight line in a plane

Thanks Mark44, I had forgotten the negative reciprocal rule of slopes for perpendicular lines. Everything makes sense now.
19. ### Straight line in a plane

The title does not say much. But my actual question is as follows. Let us suppose a line ax+by=0. This means A.B = 0 with A and B being vectors, where A = [a,b] and B = [x,y]. Therefore, A is perpendicular to B. Now my question is if A is also perpendicular to line ax+by=0 (I'm not sure if this...
20. ### What is an integrating factor exactly?

I'm sorry about the question not matching the title. I didn't realize when posting it. Your guess sounds right. Thanks.
21. ### What is an integrating factor exactly?

While solving non-homogenous linear ODEs we make use of the integrating factor to allow us to arrive at a solution of the unknown function. Same applies to non linear ODEs where the ODEs are converted to exact differentials. But what I don't understand is how and why would someone have come up...
22. ### Current issues faced by the aerospace industry

I was mainly looking for issues being faced by the commercial aviation and the spacecraft industry.
23. ### Current issues faced by the aerospace industry

Hello everyone, I wanted to learn about the issues that the aerospace industry is currently facing. Could anyone please help me in this regard. I searched on the internet but could not find a proper web site that explained this. So I thought this forum was the right place to ask about this...
24. ### Concept of limit

Well, I actually had a fundamental doubt (silly even) for which reason I had posted the question mainly. I am a newbie to the concept of limits. My doubt is as follows. Why should we look to modify the numerator or the denominator or both? Why not just consider that as n tends to infinity the...
25. ### Concept of limit

How can it be proved that as lim n tends to infinity, (n2-1)/(n2 + n + 1) tends to 1 ?
26. ### Help with deriving time, velocity, displacement

Sorry. A small correction in my previous reply. t is not velocity*distance.
27. ### Help with deriving time, velocity, displacement

I don't understand why you used 2(-Vi-Vf)d=t t is not velocity/distance if there is acceleration. I am assuming the acceleration to be a constant here. Use the laws of motion to find the acceleration. Once acceleration is determined it is easy to find how long the dog took to reach a final...
28. ### Representing ratios with division

Ratios between two quantities give us the comparison of a quantity with a unit value of the other quantity. Now lets say a bag contains 10 oranges and 5 mangoes. the ratio is 10:2 or 10/2 = 5. That is, for every one mango we have 5 oranges in the bag or we can say 5 oranges per mango. Same...
29. ### Why are transcendental functions called so?

I see. Thank you pwsnafu.
30. ### Why are transcendental functions called so?

I have learnt that they are called so because they cannot be expressed with the help of elemental methods of mathematics such as addition, subtraction, multiplication and division. But then isn't the whole of mathematics itself based on the elemental methods?