A sine wave or sinusoid is a mathematical curve that describes a smooth periodic oscillation. A sine wave is a continuous wave. It is named after the function sine, of which it is the graph. It occurs often in both pure and applied mathematics, as well as physics, engineering, signal processing and many other fields. Its most basic form as a function of time (t) is:
where:
A, amplitude, the peak deviation of the function from zero.
f, ordinary frequency, the number of oscillations (cycles) that occur each second of time.
ω = 2πf, angular frequency, the rate of change of the function argument in units of radians per second
φ
{\displaystyle \varphi }
, phase, specifies (in radians) where in its cycle the oscillation is at t = 0. When
φ
{\displaystyle \varphi }
is non-zero, the entire waveform appears to be shifted in time by the amount φ/ω seconds. A negative value represents a delay, and a positive value represents an advance.
The sine wave is important in physics because it retains its wave shape when added to another sine wave of the same frequency and arbitrary phase and magnitude. It is the only periodic waveform that has this property. This property leads to its importance in Fourier analysis and makes it acoustically unique.
Homework Statement
While doing a physics assignment today, I came up with an expression in my answer that appears to be equivalent to sin(θ), however, i couldn't find a way to manipulate the expression to prove that it was. Could anyone point me in the right direction as to a way that I could...
First off, this is NOT a homework question! That is, I'm not doing this for any course. So then, here's the question:
I have some data points to which I fit a sinusoidal curve. I get the best (min) chi-square. Now, the question becomes how good a fit is my sinusoid? I was thinking that I...
Hey guys. I am trying to simulate some circuits in MATLAB's Simulink, and I always get some weird graph which is not sinusoidal at all. I wanted to know if anyone could tell me which block am I missing if I want to get a good sinusoidal wave.
Here are the pictures of the circuit and the...
Homework Statement
http://www.wifstrand.se/Albert/stuff/p7.7-1.png
Homework Equations
vL = L * (diL / dt).
All of the inductors can be reduced to a single 8 H inductor, so
iL = (6 / 8) * ∫ cos 100t dt = 0.0075 sin 100t
if you integrate from 0 to t.
The Attempt at a Solution
The formula...
Homework Statement
Homework Equations
ω=2\pif
The Attempt at a Solution
After converting it from time domain to phasor domain
my answer is I=17.6\angle25mA.
How am I suppose to show the current at time = 2 sec? Do I just plug in 2 and find the sine of it?
Homework Statement
Consider an underdamped harmonic oscillator (Q > 1/2) with a sinusoidal driving
force Focos(ωdt).
(a) (5 pts) By using differential calculus find ωd that maximizes the displacement amplitude.
(b) (7 pts) By using differential calculus find ωd that maximizes the velocity...
Hi,
I have a bunch of spectra which happen to show some sinusoidal baselines, like this:
I would like to subtract these baselines somehow. Of course I can try to fit sinusoidals using for instance Matlab's lsqcurvefit, but it seems like I have to be very careful with my input guesses not to...
an independent source with a forcing function modeled by cos(500t) is in series with an 100 ohm resistor. A dependent (current controlled) source is placed across the remaining resistor terminal and ground. A 0.3mH inductor is in parallel with the dependent source. The value of the dependent...
Why/How does a linear oscillator give >>>sinusoidal<<< output?
I am basically confused how the sinusoidal signal output generates from a random noise? Why sinusoidal and not something else?
Can this be explained from the characteristic equation/circuit poles?
1. Hello everyone, I am having some trouble determining precise phase shifting by observing the graphs.
book says this graph has horizontally shifted to the right by 15 units. How was this determined? I can't figure it out!
second this graph:
Says the graph was shifted 80 units to the...
Hey forum, thanks in advance to anyone who can explain this to me!
Homework Statement
Find the derivative of each of the following:
h(x) = 3e^sin(x + 2)
The Attempt at a Solution
My friend and I worked through this together and solved for:
h’(x) = (3e^sin(x + 2))(cos(x + 2))
Using...
Homework Statement
f(x) = cos2x - sin2xThe Attempt at a Solution
f'(x) = (2cosx)(-sinx) - (2sinx)(cosx)
f'(x) = -2cosxsinx - 2sinxcosx
This is what I think the answer should be, but the back of the book says otherwise. I need help identifying what I did wrong.
Homework Statement
An object with mass 0.222 kg is hung on a spring whose spring constant is 86.4 N/m. The object is subject to a resistive force given by -bv, where v is its velocity. The ratio of the damped frequency to the undamped (natural) frequency) is 0.886. If this system is subjected...
When you have a magnet moving up and down a coil. The magnet cuts the field lines. Which generates an AC current in the coil. In my exam, there was a sinusoidal curve showing the generation of AC current. When the curve crossed the x-axis, that point was labelled X.
Now at that point was the...
has any work been done trying to understand the properties of long chains of oscillatory functions?
like f(x) = sin(sin(sin(sin(cos(sin(cos(x))))))) for example, or something like e^e^e^e^e^e^e^e^e^e^z)
So I'm currently reviewing for my electromagnetism class, but I do not remember the techniques from going to phasor to instantaneous time. Maybe someone can explain to me what is going on.
Homework Statement
Find the instantaneous time sinusoidal functions corresponding to the following...
Suppose that a spaceship is fired into orbit from Cae Canerveral. Ten minutes after it leaves Cape, it reaches its farthest distance north of the equator, 4000 kilometers. Half a cycle later it reaches its farthest distance south of the equator (on the other side of the Earth, of course!), also...
Hey, could anyone explain how you would preform a sinusoidal test on large vehicle (weight>40 tons). I have a graph from sinusoidal data, but i don't understant how they were able to obtain this information because there is not a powerful enough testing device.
Homework Statement
Measurements of the height h(t) of water in a harbor are recorded ,where h is measured in meters and t in hours.It was noted that the rise and fall of a tide is modeled by a sinusoidal function giving the height by : h(t)=a+bsin(kt+c).
(a) Obtain values of the...
Homework Statement
A sinusoidal wave is propagating along a stretched string that lies along the x-axis. The displacement of the string as a function of time is graphed in the figure (attachment) for particles at x=0m and x=0.0900m.
(A) What is the amplitude of the wave?
4mm
(B) What is the...
Question:
1. A clock is hanging on wall. length of minute hand is 16cm and the length is 8cm for the hour hand. The highest that the tip of the minute hand reaches above ground is 265cm.
a) What is equation of axis, amplitude & period in minutes of function that represents the tip of hour...
Homework Statement
The sinusoidal current i1(t) has a phase angle of 60 degrees. Furthermore, i2(t) attains its positive peak 0.25ms earlier than the current in i2(t) (i.e i1(t) leads i2(t)). Both currents have a frequency of 500 Hz. Determine the phase angle of i2(t)
Homework Equations...
Homework Statement
I know the rms of a half wave is half the peak value. But the peak value is not given to me. Instead, the V(t) function of 4cos(20pi(x)) is given. Also the period T = 100ms
Homework Equations
vrms = vpeak/2
But the peak is not given!
The Attempt at a Solution...
Homework Statement
At a seaport, the depth of the water h metres at time t hours during a certain day is given by this formula:
Q: What is the maximum depth of the water? When does it occur?
Homework Equations
h = 1.8 sin 2pi [(t - 4)/12.4] + 3.1
The Attempt at a Solution
4.9 = 1.8sin 2pi...
Homework Statement
Wave functions:
y_1=2.00sin(20.0x-32.0t)
y_2=2.00sin(25.0x-40.0t)
The units are centimeters and seconds. What is the positive x value closest to the origin for which the two phases differ by \pm\pi at t=2.00 s
The Attempt at a Solution
My understanding is...
I am trying to find the indicated currents for the following circuit, given v1 = 2sin(2t + 45):
I attempted to solve it in the following way:
v1 = 2sin(2t+45) // given
= 2[sin(2t)cos(45) + cos(2t)sin(45)]
= √2[sin(2t) + cos(2t)]
I use a matrix for the loops:
A =
[2 -1 -1
-1 3 -1
-1 -1 3]...
Hello guys :),
I have a question which I think is very advanced and weird. But I need the answer for some signal analysis purpose.
As we know, the derivative of a sine function, per se, shifts the phase, by Pi/2; i.e.,
f(x) = A sin (w t)
df(x)/dt = A sin (w t + Pi/2) = A cos(w t)...
Homework Statement
A continuous succession of sinusoidal wave pulses are produced at one end of a very long string and travel along the length of the string. The wave has frequency 36.0Hz, amplitude 5.50mm, and wavelength 0.635m.
a) How long does it take the wave to travel a distance of 8.50m...
Light is always considered to be a sinusoidal or harmonic wave without giving any reason. Maxwell's equation says that light is an EM wave but does not say its a harmonic wave or even a periodic wave.
People say that every periodic or non-periodic function can be broken down as a sum of series...
Phase shift and sinusoidal curve fitting - Finding...
Homework Statement
"Find the period, amplitude, and phase shift of each function. Graph each function. Be sure to label key points"
y = 4sin(2x - pi)
Homework Equations
The Attempt at a Solution
So, I got...
Homework Statement
Three sinusoidal waves of the same frequency travel along a string in the positive direction of an x axis. Their amplitudes are y1, y1/3.0, and y1/4.0, and their phase constants are 0, \pi/4.0, and \pi, respectively. What are (a) the ratio of the amplitude to y1 and (b) the...
Homework Statement
Hi,
Have completely forgotten how to prove that a sinusoidal waveform is periodic and can't seem to find it anywhere. So was hoping someone could here.
I've got the signal x(t)=cos(2t+pi/4)
and am trying to prove it is periodic.
Homework Equations
wt=theta
f(x+k)=f(x)...
Homework Statement
I am tasked with solving the QHO with a sinusoidal perturbing potential of the form VoSIN(BX). I need to find the ground state energy as well as the ground state eigenket |g>.Homework Equations
H_{o} = \frac{P^{2}}{2m} + \frac{1}{2}m \varpi^{2}
H = H_{o} + Asin(BX)...
I have impedance values for an electrode (used for nerve stimulation) over a wide frequency range using sinusoidal current. Now I have to calculate how much voltage I need to stimulate the electrode at a current of 5mA, using the equation (V=IR). I have to use monophasic pulse train of 5 to 10...
Homework Statement
Two transfersal sinusoidal wave of amplitude 0.5 cm and 8 cm wavelength traveling in opposite
directions along the wire. Wave speed in the wire is 1.2 m / s. Write the equation of these two transfersal wave equation and find the resultant wave. Draw the shape of wire at time...
Homework Statement
I can find the graphs amp and period. The only problem is finding the sub points or sub intervals. Say...
Y = 3 sin (4x)
Amp = 3
Period = 2pi/4 = pi/2
But.. don't know how to get the key points of the sub interval. The textbook says I have to divide interval [0...
in a sinusoidal circuit, only the resistive part gives the average power. so why is the load impedance the conjugate of thevenin resistance, consisting of both the resistive part and inductive part, required for maximum average power?
Homework Statement
In my electromagnetics book, in the section that talks about loss tangents, the equation for average power dissipation per unit volume is P=(1/2)*J*E (W/m^3). What does the coefficient of 1/2 come from? Earlier in the book, it gave the differential power dissipation dP=...
I'm just looking for some sources that would help me deduce values from the instantaneous value of a sinusoidal voltage. For example I have a question that states it as:
v = 50cos(100*pi*t - (pi/3))
I just need some material to help me deduce things such as the following:
* the peak to...
1. An oscillator with mass 0.5 kg, stiffness 100 N/m, and mechanical resistance 1.4 kg/s is driven by a sinusoidal force of amplitude 2 N. Plot the speed amplitude and the phase angle between the force and speed as a function of the driving frequency and find the frequencies for which the phase...
hey everybody
how are you ?
hope everyone's fine
well , i have this problem related to electrical circuits
Homework Statement
A group of small appliances on a 60 Hz system requires 20kVA at 0.85 pf
lagging when operated at 120 V (rms). The impedance of the feeder
supplying the...
I have a word problem with the equation being:
h=1.55cos[360/12(t-10.75)]+2.7
Then it says let h=3.2, how do I solve this?! All I can do is take away the 2.7 and put it on the other side, but then what?
Homework Statement
Prove that if a transverse sinusoidal wave is traveling along a string, then the slope at any point of the string is equal to the ratio of the particle speed to wave speed at that point.
The Attempt at a Solution
This is what i did isn't the equation for transverse =...
Homework Statement
A sinusoidal wave of frequency 50Hz travels along a string at a velocity of 24m/s. At a given instant the displacement and velocity of a certain point in the string are 22mm and 1.6m/s respectively.
Taking the certain point and given instant to be x=0, t=0 derive the...
I have seen many equations light as a wave but none of which have represented light as a simple sinusoidal function. I want to be able to graph light waves on a cartesian plane as one sine curve. I know that light isn't that simple but could light be represented as a 2 dimensional sine curve...
Hello, I am taking a vibrations course and we are currently talking about using PDEs to find responses of beams. In the book, there is an equation to find the natural frequencies of a simply supported beam under an axial load:
omega = (pi^2/l^2)*sqrt(EI/roA)*sqrt(n^4 + (n^2*P*l^2)/(pi^2*EI))...
Homework Statement
I need to calculate the frequency, angular frequency and period of sinusoidal vibrations in simple harmonic motion. The acceleration amplitude is 10g (98.1m s-2) and the vibration amplitude is 2cmHomework Equations
The equation I have for frequency is
f=(√(a/A))/2*pi
where a...
Homework Statement
I need to find the maximum speed of a hydraulic valve component which is attached to a vibration testing machine and subjected to sinusoidal vibrations. The values I have so far are the frequency of vibration, the period of motion, the acceleration amplitude and the...
Homework Statement
Two transverse sinusoidal waves combining in a medium are described by the wave functions
y1 = 5.00 sin π(x + 0.900t)
y2 = 5.00 sin π(x − 0.900t)
where x, y1, and y2 are in centimeters and t is in seconds. Determine the maximum transverse position of an element of...