Sine Definition and 521 Threads

Hi, Could someone please explain how EXACTLY a sine wave is produced using an LC filter from a PWM waveform generated by an inverter. Thanks

hey. I used to be quite talented at math, but I've let my talent deteriorate in the ~10 years since my last calculus class. I have a problem which I'm sure I would have devoured easily back in my school days, but am having trouble with now. I am considering two points on a normal (0 to...

I have noticed something strange when you take the value of sin(pi*10^-n). It approaches pi*10^-n. I have attatched the file here.

Homework Statement Two ropes are attached to a log that is floating in the water. A force of 80.0 N is applied to one rope and a force of 60.0 N is applied to the other rope, which is lying at an angle of 40° from the first rope. What is the net force on the log? We know that the angle...

hi everyone. Not really a homework question but I'm trying to teach myself trig and I wonder Why does a sine graph have x intercepts in multiples of pi and why does a cosine graph have intercepts pi/2

Homework Statement Find the limit: lim (1-cos2x)/(xsinx) x->0 Homework Equations Identities The Attempt at a Solution I've done this over and over and over again! The answer is supposed to be 0 but I keep getting 2 ): lim (1-cos2x)/(xsinx) x->0 lim...

Usually to do the remainder we take Rn(x) = (f differentiated n+1 times at a ).(x-c)n+1/(n+1)!, but when my function is sin(x) do i take (f differentiated 2n+2 times at a ).(x-c)2n+2/(2n+2)!? Thanks

If I modulate a pulse X(t) with a.) a sine wave or b.) a cosine wave, I have the frequency spectrum expressions a.) \frac{1}{2j}[X(f-f_0)-X(f+f_0)] b.) \frac{1}{2}[X(f-f_0)+X(f+f_0)] When I plot these for a pulse, I see a difference in the magnitude spectrum, but I should not expect...

Hello, I hope you can help me. I want to "alter" a sine wave. I would say "modulate", except that I was unsatisfied with the FM formula. Here's what I want, visualize this: 1) copy-n-paste an image of a sine wave into MS-Paint 2) select part of the image from wave top1-to-bottom1 3)...

What happens when you add two sin functions for example: y=sin(x) + sin(2x) ***additional questions*** how about adding more than two funtions such as y=sin(x+p/2)+sin(2x+p/2)+sin(3x+p/2)+sin(4x+p/2)+sin(5x+p/2)+sin(6x+p/2)+sin(7x+p/2)

I have yet to see or understand the benefit of knowing the cosine and sine sum and difference of two angles identity... can someone please explain why you would want to break up one angle into two angles... then solve from there... does not make sense to me... just use a calculator.

Hi! I recently bought an inverter that connects to a 12 volt battery and gives out 220volts AC current. It is rated at 1200W and it produces modified sine wave. The main question I am trying to solve is: Is it safe to run my laptop and dsl router on this modified sine wave? I have done a...

Homework Statement Please see the attached picture. I need help finding the angular frequency. The answer is 1571 but I don't know how they arrived at the solution. From the picture it looks like the period is 2pi but this would give an angular freq. of 1. Homework Equations...

Hello, I was following the derivation of the solid angle of right rectangular pyramid that I found at http://www.slac.stanford.edu/~bgerke/notes/solid_angle.pdf" . I don't quite understand the step between the 3rd to the 4th equation. In particular how the integral...

Homework Statement Hecht in his optics mentions that Asin(kx-wt+pi) is equivalent to Asin(wt-kx) w=greek omega Homework Equations What is the fundamental reason behind this? The Attempt at a Solution I have a hunch it's plain trigonometry applied, but none of the things that I can...

Homework Statement Find the solution u, via the Fourier sine/cosine transform, given: u_{tt}-c^{2}u_{xx}=0 IC: u(x,0) = u_{t}(x,0)=0 BC: u(x,t) bounded as x\rightarrow \infty , u_{x}(0,t) = g(t) 2. The attempt at a solution Taking the Fourier transform of the PDE, IC and BC...

niagra falls skywheel, a ferris wheel has a diameter of 50.5 m and rotates 1 revolution in 2 minutes. the lowest point on the wheel is 2.5 m from the ground. This is the equation i have come up with, please tell me if this is right or not, and if it is not please come up with your own...

How do i distinguish between a cosine and sine function simply by looking at the graph? Usually its easy because the graph for the base sine and cosine functions have certain distinctive features(like cosine function intercepts the y-axis at 1 usually) and the sine function hits the origin(0,0)...

Homework Statement In Example 3 under Theorem 2.5 of Apostol's Calculus Volume 1, I don't understand how the final formula on the right is obtained.Homework Equations The identity cos 2x = 1 - 2 sin2 x implies sin2x = 1/2(1 - cos 2x) so, from Example 2, we obtain: \int^a_0\,sin^2\,x\,dx =...

How Do i find the zeros for this particular sine function? y=asin(k(x-d))+c when we are given a K value i know how to find the zero but when we are not, i don't know how to find the zero(Atleast after everything has been horizontally, and vertically shifted and streched) y=2sin(x-30...

Graph the function y=cosx-2I have already graphed this, there are several methods to solve this, i opted to use table of values to find all the coordinates to y=cosx, then moved all the y coordinates of each point 2 units down, and the y int was at -1...would this method result in the correct...

Homework Statement Two alternating voltages are given by: V1= 12 sin 200pi t V2= 18 sin 200pi t + pi / 3 i) Plot each wave form on the same axis for one complete cycle ii) Add both together and plot the resultant waveform on the same axis iii) Using complex numbers, confirm ii)...

1. Homework Statement I am doing a project for my precalc class which explores the applications of sine waves in real life. I chose to do bat and dolphin echolocation. so far the information i have found online has given me frequency in Hz, length of each pulse, and intensity in db. I'm pretty...

Homework Statement Hi guys, I am having difficulty with the following problem: Show the complex sine function has real valued zeros. Homework Equations I know that sin(z) = (e^iz - e^-iz) /2iThe Attempt at a Solution I have to find roots of sin(z), i.e, when the above equation = 0. First I...

I'm trying to get a method to determine the time, t, when two sine waves added together peak, an exact solution. For instance, F(t) = sin(w1*t) + sin(w2*t) Obviously this is not really mathematically straightforward because there are infinitely many solution based on the nature of the sine...

Homework Statement Given a sine wave signal (20V PP) connected to a 10 kilo-Ohm resistor. Calculate the current through the resistor in terms of average, rms, and peak currents. What wattage rating should the resistor have? Homework Equations Vrms=(1/Sqrt(2))(Vp) V=IR The Attempt...

Homework Statement all i really need to do is solve the integral: \int-3*sin(\frac{n*pi*x}{L})*cos(\frac{8*pi*x}{L}) from x=0 to x=L Homework Equations The Attempt at a Solution I'm not very sure where to start with this. Any help would be appreciated.

Hello All, I am just wondering how to find c in the sine function (y=asinb(x-c)+d). I understand wat the values mean and how to find a b and d but c i am not to sure how to find unless there is a already given graph. thanks

Homework Statement What is the importance of knowing how to express trig ratios in terms of sine, cosine, tan, cosec, sec, or cot? Homework Equations The Attempt at a Solution

Hi i am a 3rd year electrical student, i have a limited knowledge about inverters. i am trying to make a pure sinewave inverter, my intial spec was to create a 1) boost converter dc to dc 2) 3 stage pwm using a bubba oscillator etc 3) using a filter. my supervisor for the project said i could...

Homework Statement I have two series of data consisting of samples of a noisy sine wave and need to determine the amplitude and phase and the confidence intervals. I determined the amplitude and phase but don't know how to calculate the confidence intervals, help! The Attempt at a Solution By...

Lately I have been trying to plot sine waves, but I can't understand any explanation on the net. I always get y=sine(x), but I never receive any explanation regarding what x IS, be it angle or just the x-axis number. I found a way around this using the Pythagorean theorem, but that is annoying...

Homework Statement Find simple formulas for 1+ cos(θ) + cos(2θ) + cos(3θ) + ... + cos(nθ) and sin(θ) + sin(2θ) + sin(3θ) + ... + sin(nθ) The Attempt at a Solution It's not really a homework question, but more for making a problem that I'm trying to solve a little bit more simple...

Homework Statement Hi. I need help understanding a task where i am supposed to prove that a function must be greater than 0 when x is from 0 and up. f(x) = (x-0)integral of (sinx/(x+1)) please help me out with this. Mons

hello i need to now if i can compare between two sine wave by pic 16f877A or pic 16f628A? that the input of pic become sine wave , can the pic read that wave or can generate it? how i can do this ? Any ideas?

Hi guys, I need to convert a sine wave to square wave, sine wave is running at about 1.5 GHz, so I had an idea of using comparator, but I am afraid that most of the conventional op-amps can't support my speed requirement. Any advice and reference circuits please.

Kind of new to this stuff, so hopefully you guys will bear with me. So a simple Oscillator with a Capacitor and Inductor... I understand that the energy flow causes the inductor to generate and collapse a magnetic field. I also understand that Sine waves are generated by changing the...

Dear All I want to design a 1MHz sine wave oscillator to be used as carrier wave for Amplitude Modulation. Which will be the best approach in terms of frequency and amplitude stability and why? Can the technique be implement using high slew rate op amp and also can we use crystal...

The 4th derivative of a sine wave is itself. This, of course, not only is a fact, but can be used to define the sine wave. My question is, are there any theories relating the abundance of sine waves in QM to the fact that the largest dimensions of space-time are together 4 dimensional? For...

Hi All I'm in the process of developing a phase control circuit. I need to know the specific time that corresponds to a required % of max power to chop the sine wave of a mains. I know that there is someway of calculating the time interval for a percentage power using integration or some form...

[b]1. This is the given data table --------Jan----Feb----Mar---Apr----May----Jun----July----Aug----Sept----Otc----Nov----Dec Maximum:33.2--32.2--31.2--28.9----25.4----22.2--21.9----23.9----27---- 29.8----31.7----32.9 This is a temperature table and i need to find its sine equation.b3/ y=...

Does anyone know a Sine Wave Generator program that will plot Excel Data and extrapolate a a sine wave with its harmonics? I know MatLab will connect but will not make a fluid sine wave. Freeware suggestions welcomed. Any suggestions?

Hello, Am trying to make dc/ac inverter with pure sine wave output, while am searching i found an IC which is SG3524 which can generate a pwm signal. Is it a good choice for pure sine wave output, and what is the difference between the pwm signal generated by micro controller and the pwm...

hi every one, i have one doubt i studied abt trignomentry. there finding the triangle angle or side of the triangle using sine function. if we are taking right angle triangle sine A = opp/hypo, cos A = adj/hypo and tan A=opp/adj. here we are finding angle for A only why we are having three...

Hello! This is a quick question more to do with understanding. When using a sine substitution in an integral, such as: \int \sqrt{a^2-x^2} dx Using the substitution x = a sin{t} Don't you 'lose' some information? Because the range of values for x can be from neg. inf. to pos...

sin x = 0.5299 cos x = 0.8480 Without using inverse cos or inverse sin, is it possible to calculate the angle?

a.cos(wt) + b.sin(wt) = M.cos(wt + ϕ) Can you give me M and ϕ in terms of a and b?

[PLAIN]http://img266.imageshack.us/img266/8206/triangles.png This is not a homework question, but it is something I can't wrap my mind around. What is the equation for sine alpha where alpha is greater than 90 degrees? For the first triangle its easy: sine alpha = b/c But what is it for...

In physics lab we were using a signal generator with sine wave to find the frequency of a circuit quite precisely. Unfortunately, we had trouble and when checked with a circuit with purely resistive impedance, voltage changed with the frequency of the sine wave. The signal generator is...

Homework Statement What would be the best method to approach this integral? And then solve it. \int\frac{dx}{(sin[x]+2)^2} At first, I thought it would yield to the substitution of u = sin[x] + 2, with du = cos[x]. But this doesn't completely change the integral to one of u. Now, I don't...