Amplitude Definition and 825 Threads

Homework Statement What is the electric field amplitude at a distance of 0.67 m from a 90 W lightbulb? Assume all the power of the bulb goes into light of a single color with lambda = 500 nm and assume the bulb produces a spherical wave. Homework Equations I don't know what equations...

If the intensity of an electromagnetic wave is 80 MW/m^2, what is the amplitude of the magnetic field of this wave? (c = 3.0 x 10^8 m/s, permeability of free space ''miu subzero''= 4π × 10^-7 T ∙ m/A, permittivity of free space ''E subzero'' = 8.85 × 10^-12 C^2/N ∙ m^2) 80MW/m^2= 80,000,000...

Does changing the angular frequency change the amplitude of a forced oscillation? If so, I don't understand how that can be. I guess that the angular frequency is based only on the springs and dampers? So assuming those are the same then the angular frequency will always be the same? Are...

If you take the absolute value of the FFT output, does that give you the amplitude? I am asking because I have seen example where that is taken as the amplitude, and examples were the absolute value is multiplied by either SQRT2 or by 2 to get the magnitude. So my question is what is...

N = 1/2 E0 √(ε/μ) so E0 = √2*N*(ε/μ) where the value of ε/μ is 376.7Ω I have a similar question to this, below, regarding amplitude of an oscillating magnetic field. Yes, I'd like the answer, but am initially stuck deciding whether the mW is milli- or mega- Homework Equations A laser...

Homework Statement I have decay of Higgs to fermion and antifermion and I need to find out the invariant, averaged amplitude. And I wrote down the Feynman diagram, and calculated everything and I came to this part: \langle|M|^2\rangle=\frac{g_w^2}{4}\frac{m_f^2}{m_w^2}(4p_1\cdot...

Hello, I have worked out some force diagrams for forced oscillations and ended up with the solution as : mx_double_dot+rx_dot+kx=Pcos(Ωt) I am now asked to work out the amplitude. I know all of the variables except frequency(Ω). What equations can I use to find that? Thanks.

I know in classical physics we calculate the energy based on the Amplitude. I also know we calculate the energy in QM based on Frequency. I know also that it was experimentally deduced that it is the freq. based on the photo electric effect...and so on... What I'm interested is in the...

I have a steel drilling Derrick 240 feet high mounted central to a ship, this is used for drilling for oil. Calculations have been done on the Derrick in regards to reaction forces in different modes of operation(drilling, transit etc). I need to do a vibration analysis of different points on...

A body moving with simple harmonic motion has an amplitude of 1 meter and the time for one complete oscillation is 2 seconds . Determine the velocity and acceleration of the body after 0.4 second from the mean position ? this is the answer : Vx = w root(r^2-x^2) ax=w^2.X w= 2Pi/t =...

I am curious about the complex nature of the amplitudes used in Schrodinger's equation, and what (if anything) it means physically. I ran across this topic being discussed sometime in the past on this forum, and several posters alluded to some deep significance to this fact, but didn't...

Homework Statement A baby bounces up and down in her crib. Her mass is 10.5 kg, and the crib mattress can be modeled as a light spring with force constant 654 N/m. The baby soon learns to bounce with maximum amplitude and minimum effort by bending her knees at what frequency? b)If she...

I thought that the frequency was constant for AM modulation, and just the amplitude was modulated. So why are there a range of frequency's (side bands around the baseband) when the signal is plotted on a frequency domain graph?

I have now in some time tried to figure out a way to calculate the peak amplitude of a water wave, after starting the wave motion by dropping an object, with a certain weight from a given height, in the water. I am not in need of the information, but it would be nice to know. I will hope...

Homework Statement A high pass filter tuned for a corner freq. of 40 000 rad/sek and with a damping coeffisient of 1/sqrt(2) is being subjected to a square wave voltage with amplitide of 1 volt and 8000 rad/sek. What is the amplitude of the fifth harmonic on the output side of the filter...

Homework Statement What physical phenomenon requires us to work with probability amplitudes rather than just with probabilities, as in other fields of endeavour? Homework Equations The Attempt at a Solution That the probability of an outcome is given by the square of the modulus of...

First off let me state that I'm just a mechanical engineering student, so I'm not too savvy when it comes to quantum physics, but my teacher was talking about this equation in class and it reminded me about infinite wavelengths near the egde of the universe and the event horizon on a black hole...

Hey Everyone, Can someone explain to me the natural of amplitude modulation in regards to sound. As in one modulator frequencies' amplitude modulating the amplitude of a carrier frequency. Because at low frequencies the modulator only affects the carrier in a way that makes its volume go up...

Hey everyone, I am trying to understand the phenomena behind the technique of using amplitude modulation in sound synthesis. When you have two frequencies, for example, w1=200hz and w2=300hz, and you use the amplitude of one (w1) to modulate the amplitude of the other (w2), it creates 3...

For a wave traveling from a medium with refractive index n1 to n2 with n2 > n1, the amplitude reflection coefficient is given by: r = (n2 - n1)/(n2 + n1) Consider a beam of light passing through a single pane of glass. There is a reflection at the front surface of the pane, with the...

I'm not exactly sure what it means when my book says that the wave function ψ(x,t) is a probability amplitude of knowing where the particle is in position x at time t.

Hi, I want to calculate the amplitude of the following: V(t) = Acos(2wt)+Bcos(3wt)+Ccos(4wt)+Dcos(5wt) Not really sure what approach I can take to do this. I was thinking of using some combination of the double angle formula to simplify each part, but I don't think that will necessarily...

Homework Statement This is a horizontal mass spring system in a simple harmonic motion problem set. Vmax = 20 m/s F = 10 N m = 0.5 kg Find Amplitude (A) and spring constant (k) Homework Equations The Attempt at a Solution I could not figure out a way to solve this problem, and the only...

Homework Statement You stick two blocks together with Velcro. The manufacturer rated the Velcro as needing a force of 50N to separate the side you are using when applied to solid surfaces. You set up the connected blocks so that the top one is attached to the end of a vertical spring. The...

I know that an AM Amplitude vs. Frequency Spectrum has a central frequency = carrier frequency and two side bands of carrier frequency ± signal frequency. Now what would a similar spectrum look like for an FM wave ? My textbook just says that '... further side frequencies that are...

θθHomework Statement A simple pendulum of mass 20.0 g is suspended by a length of string 1.0 m. It is pulled from equilibrium so that it's raised 10.0 cm and released. Angular position given by θ(t)=θmaxcos(ωt+∅) What is the period? What is the maximum velocity of the pendulum? What is the...

Homework Statement Prove the complex amplitude reflectance of a spherical mirror is given as exp[-jk(x2+y2)/R] Homework Equations Transmittance of a spherical mirror is also exp[jk(x2+y2)/2f] The Attempt at a Solution I have totally no idea how to go about doing this. Can I just...

consider two circuits: In circuit A the signal form mic AC (very low amplitude ) is combined with Vbb(to drive the BJT), as the two voltage sources are series they adds up and its amplitude increases and it is passed to bjt and then to loudspeaker. in circuit B the signal form mic AC (very low...

Hi Guys I have a very simple and basic question. Assume interface of two dielectric mediums. If the t is transmition cofficient for electricfield from medium 1 to medium 2 with refractive indexs n1 and n2, what is the transmitivity of power from medium 1 to medium 2? I know it is...

In Fourier series we have small waves on the top of big waves (the function seems like that), but the small waves do not have the same amplitude. Does somebody know how to get a function with waves and small waves on the top but with the same amplitude.

Homework Statement A string of mass 38.5g and length 5.60m is secured so that it is under tension of 220N. A wave with frequency 178 Hz travels on the string. Find the speed of the wave and the amplitude of the wave if it transmits power of 140 Watts. The Given answers are: 179 m/s and 1.35 cm...

Two waves are perfectly superposed (traveling same direction), but are 90 degrees out of phase. Does this result in destructive or constructive interference, as the waves could be seen as either half anti-phase or half in-phase. For example, the first wave has an amplitude of 1. The second wave...

Homework Statement from a line source, if amplitude of a wave at a distance 'r' is'a'.then the amplitude at a distance '4r' will be what? The Attempt at a Solution i could not understand the pattern of the spreading of the wave from the line source.

It’s very well know that Maxwell equations bring the solution for plane waves but as far as I know I cannot use them to detect how the field would evolve by only looking the E and B fields on the contour of the point under evaluation. Is that possible? My question comes because on a plane wave...

Homework Statement You are told that, at the known positions x_{1} and x_{2}, an oscillating mass m has speed v_{1} and v_{2}. What are the amplitude and angular frequency of the oscillations? Homework Equations x(t) = Acos(wt - \delta) v(t) = -Awsin(wt -\delta) w =...

Have a look at http://arxiv.org/abs/1202.5039 Degenerate Plebanski Sector and its Spin Foam Quantization Authors: Sergei Alexandrov (Submitted on 22 Feb 2012) Abstract: We show that the degenerate sector of Spin(4) Plebanski formulation of four-dimensional gravity is exactly solvable and...

Like photons, all particles have a wave/particle duality, so when energy is added to an electron, say in a particle accelerator, why does the "amplitude" of the electron wave never increase (say as an increase in the actual number of electrons) - why is it that the energy added always just comes...

Homework Statement Calculate acceleration and velocity of a piston. Stroke is 150mm and engine speed 3500rpm Using simple harmonic motion equations Homework Equations a = -ω^2*s v = ω*√A^2 - s^2 ω = 2*∏*f v = velocity, a =...

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...

Homework Statement Basically we were given the attached picture and we are supposed to find at what value for the AC frequency from the Vin will the amplitude be halved at V (CE base) Homework Equations The Attempt at a Solution I think i am supposed to use V=Iz where Z is the...

If amplitude is the measure of energy in a sound wave - On increasing amplitude, the medium particles should hit each other in lesser time because they have more force(which increases their speed) and this cycle should repeat and repeat. Eventually, the speed of sound should increase. But...

Is there any process or device that will allow a transmission of an EM wave of a certain amplitude (say 2) but will block transmission of a lesser amplitude (say 1), such that an EM wave of a given amplitude of blocked, but a EM wave with 2x the amplitude will pass thru (even if that amplitude...

When a point source emits sound, the sound travels away from the source as a series of wavefronts - all being spherical shells - away from the source right? Now, we say the energy is conserved if we neglect damping forces in the medium, and so the power delivered by the source should be...

Homework Statement You and your friend sit on the same swing and oscillate about the equilibrium position. Your friend falls off the swing exactly at the highest point (largest amplitude). What will happen to the amplitude and frequency of your oscillation ? (a) the amplitude stays the...

A particle moves with SHM of amplitude 10 cm and a maximum speed of 0.5 m/s. ...find the objects period

I just saw a few of Feynman's lectures on QED: Reflection and transmission, and he describes the concept of probability amplitude arrows, and their representation as vectors, from what I interpreted, the length of the arrow is proportional to the probability of an event, and its angle is...

1. Homework Statement [/b] Consider the damped oscillator illustrated in the figure below. Assume that the mass is 365g, the spring constant is 112N/m, and b = 0.117kg/s. How long does it take for the amplitude to drop to half its initial value? (A*e-b*t/(2m))...

Homework Statement An object in SHM oscillates with a period of 4.0 s and an amplitude of 10 cm. How long does the object take to move from x = 0.0 cm to x = 6.0 cm? Homework Equations T = 2*pi/w x(t) = Acos(wt) or x(t) = Asin(wt) The Attempt at a Solution T = 4.0 s A = 0.10...

Hello, I am trying to understand how the most basic form of AM works. Can someone please confirm if my brief description below is essentially correct ? I know that upper and lower sidebands are created when a signal is modulated onto a carrier frequency. These sidebands result in a signal that...

Would it just be the energy of the wave (i.e. E = hf)?