Amplitude Definition and 868 Threads

The amplitude of a periodic variable is a measure of its change in a single period (such as time or spatial period). There are various definitions of amplitude (see below), which are all functions of the magnitude of the differences between the variable's extreme values. In older texts, the phase of a period function is sometimes called the amplitude.

View More On Wikipedia.org
Recent contents Top users
  1. rc2008

    Max amplitude of superposition of 2 waves

    My answer is simply 4.6+ 3.2 = 7.8m , correct me if I am wrong. If it's 4.6 ##\cos(2\pi*5.4x)## and 3.2 ##\sin(2\pi*10x)##, then the max amplitude should be sqrt(4.6^2 + 3.2^2) = 5.6m, correct me if I am wrong.
  2. kirito

    what the relation between the amplitude magnitude and mass at resonance?

    should I be expecting a higher amplitude at resonance for a mass that's heavier to an extent form another where each is attached to a spring vertically , I assumed that's true since the heavier mass will stretch the spring more meaning when moving like a sin or cos wave the amplitude...
  3. S

    Intensity of central maximum when width of single slit is doubled

    My answer is (D) but the correct answer is (B). I thought the intensity will be 4 times since the slit width is doubled and amplitude becomes twice. What is my mistake? Thanks
  4. M

    Can the Voltage Across a Capacitor Be Greater Than the Source Voltage in a Series RLC Circuit?

    (a) Substituting the values, I get ##X_L=100\ \Omega##, ##X_C=666.67\ \Omega##. From this, I get ##Z=601\ \Omega##, ##I=49.9\ mA## ##V_R=9.98\ V##, ##V_L=4.99\ V##, ##V_C=33.3\ V## (b) It's possible for the voltage amplitude across the capacitor to be greater than the voltage amplitude across...
  5. heroslayer99

    When Do Sand Particles Slip Off a Vibrating Plate?

    A horizontal metal plate connected to a vibration generator is oscillating vertically with simple harmonic motion of period 0.080 s and amplitude 1.2 mm. There are dry grains of sand on the plate. The frequency of the vibrating plate is kept constant and its amplitude is slowly increased from...
  6. K

    I Why does wave amplitude indicate particle location in QM?

    Why do we say that wave amplitude tells us where we are likely to find the particle versus where we are likely to find the wave from the particle? Isn't the later a more accurate description of the QM math?
  7. S

    Seeking advice on "simple" pendulum problem

    [Mentors' note: moved here from the technical forums after the thread was already fully developed, so no HW template] Hello all! I have a problem which I am beginning to suspect I am either unequipped to solve, or which does not have enough details! I can see, in my mind, the problem, but I...
  8. ab200

    Constructive Interference from Speakers on an x-axis

    The first part of this question asks for the maximum amplitude produced, which I found to be 12.86 Pa. I was able to set up the expression for the combined wave equations. However, I am struggling to understand how to set up and solve an expression to find the distance I could move one of the...
  9. DuckAmuck

    I Calc Ampl & Cross Sec: Electron + Positron to Photon + Z Boson

    Looking to calculate the amplitude and cross section of the process: electron + positron to photon + Z boson. Basically the annihilation resulting in Z + gamma rather than gamma +gamma. My question is mainly about how to deal with the polarization states with the Z boson, since there are 3 and...
  10. M

    Electric field amplitude question regarding intensity calculations

    My question is specifically with calculating the intensity. The book solution is I=P/(4*pi*r^2) but would this not give me a weaker electrical amplitude in the final calculation after plugging it in to I=(1/2)*√(ε0/μ0)*(E02) ?
  11. jaumzaum

    I Amplitude of the maximums in single slit diffraction

    Hello! I was trying to calculate the amplitude of the secondary maximums in the single slit diffraction. When I use the formula: $$ I = I_0 (\frac {sin(\Delta \phi /2)} {\Delta \phi /2})^2 $$ If I take ## x = \Delta \phi /2 ## and derivate I get that the maximum occurs when: $$ x = tan(x) $$...
  12. homeworkhelpls

    How is Wave Intensity Affected by Half Amplitude and Double Frequency?

    TL;DR Summary: How do i find the intensity of this wave? I know I is proportional to amplitude / frequency squared, but I don't know what equation this comes from. And I don't know how to answer this.
  13. J

    Calculating Wave Amplitude & Wavelength in Water Pools

    How would we model/calculate the circular waves in a pool of water (wavelength and amplitude) from a mass falling into it from a given height, and from a fountain of water falling into it continuously? Is there is a way to describe the initial configuration of the wave based on the stimulus...
  14. M

    Amplitude of a circular ripple at distance r from source

    For this problem, The solution is, Does anybody please know another way to solve this problem? EDIT: Why do they assume that no energy is absorbed by the water? Many thanks!
  15. DannyLouis888

    A physics PhD students addicted to Computational Languages

    I am a 4th-yesr PhD student in Theoretical Particle Physics. My work frequently involves computational stuff so I feel like addicted to developing and using computational techniques for solving physics problems. I am aimed at some topics involving computers for my postdoc. My current project...
  16. Ennio

    A Calculate the exact or approximate length of one period of the wave function

    The known expression of the wave function is where A is the amplitude, k the wave number and ω the angular velocity. The mathematical definition of arc length for a generical function in an interval [a,b] is where, in our sinusoidal case: For our purpose (calculation of the length in one...
  17. link223

    Max amplitude of a diving board that will not toss a pebble off?

    How am I supposed to solve this problem? I did it in a way that's analytically not correct at all lol.. As a first I was thinking about how to relate it to the motion equations to no avail.. (of course with having the condition that normal force board on pebble = force of gravity on pebble)...
  18. S

    Automotive Amplitude based frequency response simulation in Abaqus

    Hi, I have inputs like displacement of a driving mechanism and then the frequency of concern . Displacement: 0.2 mm Concerned Frequency: 100 Hz I would like to evaluate a part with the input displacement applied to a node and not as base excitation. It can be sweep over the frequency range...
  19. Diracobama2181

    A Off-Forward quark-quark amplitude in momentum space

    I am having difficulty writing out ##\bra{p',\lambda}\psi^{\dagger}(-\frac{z^-}{2})\gamma^0\gamma^+\psi\frac{z^-}{2})\ket{p,\lambda}## in momentum space. Here, I am working in light-cone coordinates, where I am defining ##z^-=z^0-z^3##, ##r'=r=(0,z^{-},z^1,z^2)##. My attempt at this would be...
  20. N

    Comp Sci Amplitude of Analog Filter Question

    Question Answer;
  21. bluesteels

    A.C. power supply voltage amplitude questions

    I know that the answer for A is 31.82. But when i look up B why is it zero? can someone explain please thank you
  22. karush

    MHB -7.8.98 amplitude period PS VS graph. of cos eq

    Find amplitude, period, PS, VS. then graph. ok I think these are the plug ins we use $Y_{cos}=A\cos\left[\omega\left(x-\dfrac{x \phi}{\omega} \right)\right]+B \implies A\cos\left(\omega x-\phi\right)+B \implies T=\dfrac{2\pi}{\omega} \implies PS=\dfrac{\phi}{\omega}$ ok I wanted to do...
  23. physicsneedslabs

    Finding Spring Constant When Given Amplitude, Time, and Mass

    I averaged the masses and times (which i took the time given and divided by 10 because in the problem it says you measure the time it takes to complete 10 oscillations) then plugged them directly into the T=(2(pi)((m/k)^1/2) and got the wrong answer. This is really confusing me because I don't...
  24. dahoom102

    SHM Find amplitude from ω and x

    Hi, I have no idea what formula to use while given these values, basically, it fits no formula. Any thing could help? Many thanks in advance Correct answer is 65
  25. U

    Calculating Amplitude in Standard Model

    Hi! I'd like to ask you if my calculation of the amplitude on the mentioned process in the Standard Model is correct. The three diagrams contributing at lowest order should be where in the middle one the two Higgs boson are NOT forming a quartic interaction vertex. My attempt at calculating the...
  26. H

    Peak of the amplitude resonance curve

    Hi everyone, I'm stuck on how to show the peak of the amplitude resonance curve is at wd = w0√(1-1/2Q^2), where Q = w0/γ. My first instinct is to take a derivative of something and set = 0, but what eqn?Help?
  27. LCSphysicist

    Intensity and electric field amplitude

    Hello. I am having some trouble to understand the resolution of this question. We could easily try to calculate the electric field relative resultant at the screen. The problem i am having is about the amplitude of the electric field: Generally, we have that the intensity part dependent of the...
  28. R

    How to find the amplitude of oscillations of a string with 5 beads?

    Hi, First of all, I'm wondering if a beaded string is the right term? I have to find the amplitude of the modes 2 and 3 for a string with 5 beads. In my book I have $$A_n = sin(\kappa p)$$ or $$A_n = cos(\kappa p) $$ it depends if the string is fixed or not I guess. where $$\kappa = \frac{n\pi...
  29. Twigg

    A Imperfectly Phase-Modulated Light / Residual Amplitude Modulation

    I'm trying to understand this paper and others on the same topic. I struggle conceptually with their first equation, which is an expression for an imperfectly phase modulated optical field from an electro-optic phase modulator (EOM) that is contaminated with a little bit of amplitude modulation...
  30. S

    Amplitude of standing wave for higher frequency

    I understand the part where there will be more nodes produced because number of wave produced will increase (let say from half wave to one wave). But I don't understand the part where the amplitude will be less. How can number of nodes (or frequency) affect the amplitude of standing wave...
  31. J

    B EM Radiation Amplitude: Is Peak Related to Intensity?

    Electromagnetic radiation is propagating sinusoidal electric and magnetic fields. Are the peak amplitudes of these fields in any way related to the radiation's other parameters, e.g. its instensity?
  32. R

    Driven oscillator amplitude steady state X(t) = ##Asin(\omega t + \delta)##

    I found ## \frac{\gamma}{2} = 7##, ##\gamma = 14## ##\omega_0^2 = \omega_d^2 + \frac{\gamma^2}{4} = 25## ##\omega_0 = \omega = 25##, thus ##\delta = \frac{\pi}{2}## ##A = \frac{\frac{F_0}{m}}{\sqrt((\omega_0^2 - \omega^2)+ \gamma^2\omega^2)} = 0.04## Thus, ##X(t) = 0.04sin(25t + \frac{\pi}{3} -...
  33. L

    Amplitude of oscillation of a mass which is the pivot of a pendulum

    1) By conservation of mechanical energy we have ##m_2gl(1-\cos(\alpha))+m_1gl=\frac{1}{2}m_1v_1^2+\frac{1}{2}m_2v_2^2+m_1gl## and by conservation of linear momentum along the x-axis we have ##m_1v_1+m_2v_2=0## which gives us ##v_2=\sqrt{\frac{2m_1gl(1-\cos(\theta))}{m_1+m_2}}## and...
  34. D

    How Do Engineers Design AntiNoise to Effectively Reduce Ambient Noise?

    Summary:: AmbientNoise + AntiNoise combined calculation I am having trouble with this question: Noise cancelling headphones use both passive (insulated earphones) and active (electronic “anti-noise”) methods to nullify ambient noise. One task of a sound engineer is to design low-energy...
  35. karush

    MHB 7.8.11 Find amplitude, period, PS, VS. graph 2 periods

    $\tiny{\textbf{7.8.11 Campbell HS}}$ Find (A)mplitude, (P)eriod, PS, VS. graph 2 periods $y=3\cos(\pi x-2)+5$ by observation we have A=3 and VS=5 ok assume $\omega=\pi$ so if period is $T=\dfrac{2\pi}{\omega}$ then $T=\dfrac{2\pi}{\pi}=2$
  36. Wannabe Physicist

    Lagrangian Problem (Find Relation between Amplitude and Momentum)

    The given lagrangian doesn't seem to correspond to any of the basic systems (like simple/ coupled harmonic oscillators, etc). So I calculated the momentum ##p## which is the partial derivative of ##L## with respect to generalized velocity ##\dot{q}##. Doing so I obtain $$p =...
  37. jk7297

    A BCS energy and Cooper pair probability amplitude

    This question is for those familiar with the BCS theory of superconductivity or familiar with R.D. Mattuck's book “A Guide to Feynman Diagrams in the Many-Body Problem.” I am working my way through the book, and I am stumped by some of the problems at the end of chapter 15 (superconductivity)...
  38. J

    A Electric charge amplitude mode superconductivity

    Hello, I have a question about the Higgs mode in superconductivity. In this doc, it is said, page 12, that the Higgs mode has no electric charge. But it couples nonlinearly with the photon (in the Ginzburg-Landau theory there is a term A²h with A the vector potential and h the Higgs mode). So...
  39. K

    A Calculation of an amplitude using the Grassmannian approach (amplituhedron)

    In the following review paper on scattering amplitudes, by Elvang and Huang: https://arxiv.org/abs/1308.1697 they calculate the amplitude for 6 particles with half of positive helicity and half of negative helicity in section 9.3.2. Their matrix C (a point in the relevant Grassmannian) is...
  40. snypehype46

    Amplitude of Feynman diagram in ##\phi^4## interactions

    This is not really homework assigned to me but I wasn't sure where to post this. I'm trying to work through the book "Quantum Field Theory for Gifted Amateurs" by Tom Lancaster. I'm doing the questions on Chapter 19 to understand how to draw Feynman diagrams and work out their amplitude. One of...
  41. J

    Dampening force - find decrease in amplitude

    So first I tried to find b. 0.454=(0.6)e^((-b/(2*11.6)*50) Anyways with some natural log algebra etc. I get b = 0.129378 But when I plug this into the same equation only changing mass to 17.7 kg I get 0.4998 or 50% when the answer should be 59.6%?
  42. A

    Electromagnetic wave equation - phase and amplitude

    how we get "e^(ikr)"...? Plz ans me... Thanks
  43. R

    I Is there any physical significance to Wave Amplitude?

    I am studying Quantum physics and I'm having some problems to understand what is the Wave Amplitude since I can't find a physical significance to it. Does anyone ever heard something that come close to a physical significance?
  44. J

    Wave, given wavespeed, wavelength, amplitude - find w.

    What I chose to do was analyze what happened at x=0. At x=0 I know sin of whatever will be 0. So 0=sin(kx-wt) and since x=0, w=Arcsin(0)/t. But this doesn't make sense because the answer isn't 0, its 0.695.
  45. J

    Damped Oscillation Amplitude Decrease vs. Mass Relationship

    so what I did was e^-(1/10.1)=0.9057 and e^-(1/14.8)=0.93466 Then 0.93466/0.9057 = 1.03198, so the heavier mass dampens 1.03 times more than the lighter mass. If the lighter mass decreases the oscillation to 72.1%, then the heavier mass would be 72.1%*1.03198 = 74.4, but this is wrong. It...
  46. F

    I Is there an uncertainty between amplitude and phase in an EM wave?

    Is there an uncertainty between amplitude and phase in classical quasi-monochromatic light?(E(t)=a(t)cos(phi(t)-omega_0*t))If it exist, what is the relation between classical and quantum uncertainty(delta I* delta phi>=1/2)?
  47. R

    Can heavy objects be used to modulate light waves with small amplitude?

    Question: Can heavy objects be used to operate light waves with smaller amplitude, or waves with high amplitude be used to operate objects with small mass? This is a diagram I drew that illustrates my point. Heavy objects are meant to be celestial bodies, and the light source generates a beam...
  48. A

    MHB Does Increasing Mass Reduce the Amplitude of a Forced SDOF Oscillator?

    I'm working on a forced single-degree-of-freedom (SDOF) oscillator. I'm trying to find how an increase in mass will affect the response amplitude? I'm looking for mathematical proof explaining this reduction in amplitude. How to derive \delta x
  49. E

    Calculating Wave Amplitude and Frequency

    My attempts were these, a) 2.0% / cycle * 25 cycles = 50% So, I got half of the first amplitude which is 0.5 m (seems not right though...) b) w=2pi/T , so put 0.5 at T, I got w=12.6 cycle/sec 12.6 cycle / sec * 6.3 sec = 79.2 cycles and it is obviously not right to me... May I get...
  50. J

    Calculating the amplitude of waves in water

    Suppose I have a perfectly circular pool which is four meters in radius, two meters in depth, and filled with water. Say I drop a steel ball with a radius of five centimeters into the middle of the pool from a height of five meters above the water's surface. After three seconds, what will be the...
Back
Top