Questions tagged [displacement]
The displacement tag has no usage guidance.
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Question about Proportionality in Sound Equation (Pressure and Displacement Amplitude)
Why is intensity in terms of pressure amplitude inversely proportional to density and velocity:
$I=\frac{\Delta p_\text{max}^2}{2\rho v}$,
while in terms of displacement amplitude, it is proportional ...
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Why acceleration is not always parallel to velocity but velocity is always parallel to displacement? [closed]
Velocity is derivative of displacement :
$$\vec v=\frac{\mathrm {d\vec r}}{\mathrm dt}$$
And acceleration is derivative of velocity.
$$\vec a=\frac{\mathrm {d\vec v}}{\mathrm dt}$$
Given that their ...
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Track an object velocity in a 2D plane
I would like to track the motion (actually, I am more interested in the velocity) of an object in a 2D plane (typically 4m x 4m). The object speed is typically 10cm/s, but the mouvement may be chaotic ...
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Calculating the magnitude of the average acceleration of a clock hand
I've been stuck on the following question from Isaac Physics for quite some time now and I'm not really sure where to even begin:
The time shown on a clock changes from 4:00 to 4:30. The minute hand, ...
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Is $W = \vec{F}\cdot\vec{D}$ actually a dot product or just calculated that way?
I know that work = force times displacement with vectors ($W = \vec{F}\cdot\vec{D}$) can be calculated in the same way as a dot product, but it seems to me that it isn't really a dot product. The ...
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What's my displacement relative to my position a year ago? [closed]
Earth moves in a few different ways through the universe. Earth orbits the Sun (plus the orbit precesses), the Sun moves through the Milky Way, and the Milky Way moves through the universe.
Compared ...
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Interpretation of velocity-velocity and acceleration-acceleration curves
I am parametrizing equations of motion in the form:
$$x(t) = x_0+v_{0,x}t\\y(t) = y_0+v_{0,y}t+\frac{1}{2}at^2$$
The parametrized equation with respect to time:
$$y(x) = y_0+v_{0,y}\cdot \frac{x - x_0}...
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Is it possible to create Fabry-Pérot Interferometer with one partially transparrent and one non-transparent mirror?
In the literature sources I've found so far about Fabry-Pérot interferometer there are only example schematics of the interferometers in transmission - light source is placed from one side of the ...
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What is the literal meaning of displacement current?
I think I know what the displacement current is.
But I don't know why they use the word "displacement" exactly.
What is the literal meaning of "displacement" of the displacement ...
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Doubt in displacement time graph for a body moving with constant, negative velocity
This is a displacement - time graph of a body having constant, negative velocity.
As we can see, the angle $θ$ (in anti - clockwise direction) is greater than $270^\circ$, and lesser than $360^\circ$,...
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Question about suvat $ x = v_0t + (1/2) at^2 $ [duplicate]
I understand why we have these two terms in this equation $ v_0t $ and $ (1/2)at^2 $. The thing I don't understand is the area under velocity vs. time graph of the first term.
I get that $vt = d$ but ...
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Is the position vector an axial vector?
The displacement vector $\vec{r}_{ij} = \vec{r}_j - \vec{r}_i$ is of course a polar vector because it's completely independent of the choice of origin, but what about the position $\vec{r}$ which, by ...
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How Work Done is Calculated for Changing Direction?
I know work done is equal to product of force, displacement and cosine of angle between them. But that formula works only when we assume that the force is constant during displacement and it acts so ...
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Difference between Displacement from Equilibrum and Amplitude of SHM
I'm currently studying Simple Harmonic Motion. What is the difference between the amplitude of the simple harmonic motion, and its displacement from equilibrium?
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Car crash - distance and acceleration no friction or rotation [closed]
A small model car is released by my hand and goes down a ramp and hits a wall.
There is no friction or air resistance and the car is influenced by -9.8m/s^2 gravity.
Why does the maximum acceleration (...
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What is the direction of $\vec r_{21}$ (position vector)? towards $\vec r_{2}$ or towards $\vec r_{1}$?
The vector representation of Coulomb's law uses a vector between the position vectors of the charges at rest. However, my teacher and a few books use the convention that vector $\vec r_{21} = \vec r_1 ...
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What is the actual meaning of velocity?
There's a scenario where a car is moving between two points A and B in a way that it first goes 30m north and then 20m south in a time period of 10 seconds.
Now the speed of the car comes out to be <...
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Springs stacked on each other in series with a mass on top, is the deformation the same?
This is a practical question which I am trying to determine the life of 5 rubber pucks which act as suspensions/shock absorbers for my airplane.
Essentially 5 rubber pucks are stacked on each other ...
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Can a distance function be derived from a displacement function?
If I have some function $\vec{x}(t)$ that represents the displacement function for some object $x$, is it possible to derive a distance function $d(t)$ for that same object, representing the total ...
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What are the eigenstates of the Displacement operator?
I know that the displacement operator:
$$ \hat{D}(\alpha)=e^{\alpha \hat{a}^{\dagger}-\alpha^*\hat{a}} $$
acts on the vacuum as: $$ \hat{D}(\alpha) \vert 0\rangle =\vert \alpha\rangle $$
But what are ...
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Is average velocity equal to displacement per unit time OR displacement divided by time?
I had looked for the definition of average velocity in books like Resnick Halliday, Tipler ' Sears zemansky but no book writes average velocity as displacement per unit time although in these books ...
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How to exactly determine the position and sign in vector quantity like displacement? [closed]
I want to know how to determine the sign. I used opposite sign my answer was 32 m. This is is wrong because in displacement sign is required for direction. This is crucial otherwise all my solutions I ...
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Mass conservation in a deformed membrane in cylindrical coordinates
This is clearly an obvious question but here is my issue.
Context :
We assume an axisymmetric deformation of a membrane, and work with cylindrical coordinates $(r; \phi; y)$. At time $t = 0$ we let $r$...
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Does work done by a non-conservative force involve distance rather than displacement?
I am a new physics teacher and struggling to piece out the nuance of work calculations for my Advanced Placement (AP) students.
I feel like after a fruitful year of distinguishing between vector and ...
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Is this relationship between the radial and cartesian displacements for symmetrically axially loaded cylinders correct?
The relationship between the radial coordinate $r$ and the Cartesian $x$ and $y$ coordinate is:
$$ r^2 = x^2 + y^2 \tag 1 $$
If a cylinder is under a symmetric axial load, a displacement in the ...
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Does work done by/against friction depend on path length or displacement? [closed]
On an equipotential surface, does the work done in moving/sliding a block of mass depend only on the initial and final position or the circuitous path (notwithstanding work done by or against friction ...
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Converting Displacement-Time to Distance-Graph for Simple Harmonic Motion
An object undergoes simple harmonic motion with the position/displacement function
$$Position=\text{sin } t$$
The distance function is:
\begin{equation}
Distance = d(t)=
\left\{
\begin{array}{lr}
...
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Time integral of a time-dependent Displacement operator
The diplacement operator on a bosonic mode with creation and annihilation operators, $\hat{a}^\dagger,\hat{a}$, is usually defined as $$ \hat{D}(\alpha)=\exp(\alpha \hat{a}^\dagger - \alpha^*\hat{a})$$...
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Is the change of displacement with respect to the radius at the origin of a cylinder always equal to zero if the load is symmetric?
Consider a cylinder under dynamic uniform axial pressure as shown below.
At the radial origin exists non-zero axial displacement $u_z(t,0,z)$. I know from the mathematical definition of symmetry that ...
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How can i find the angle? [closed]
Here we have a question of a 2 dimensional movement. I know that it is needed to get its second derivatives for acceleration but then what should I do?
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Sine and Cosine Functions [closed]
So long story short, We were given a windmill to experiment with and a sensor could sense the Voltage produced and graph it concerning time. We decided to make a sine wave out of the positive and ...
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Using normal displacement instead of virtual displacement
I know that there are many posts about virtual displacement, but I want to answer the question if of: is virtual displacement is always needed to get the same results? I am going through a PDF by ...
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Motivation for definition of work [closed]
Why do we take the dot product in the work energy theorem? Consider the integral
$$\int\vert\vec F\vert\vert d\vec r\vert$$
Why don't we define this to be work done for example, instead of $\int\vec F\...
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${}$Conservative and Non-Conservative Forces
For work done by conservative forces ($W = F.S$), we consider $S$ as the displacement and not the actual path travelled. However for non conservative forces we consider the total path length and not ...
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Radial stress of a cylinder that is longitudinally excited
Consider a cylinder that is longitudinally excited on one of its ends and fixed on the other one as shown in the picture below.
In the cylindrical coordinate system, the displacement vector $\bf u$ ...
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Derivative of distance [duplicate]
I know that $speed = |\frac{\vec{dr}}{dt}|$
and first derivative of distance with respect time will be $\frac{d\vec{|r|}}{dt}|$
These 2 expressions don't seem to represent the same thing. But when I ...
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What is exactly the electric displacement?
I found a lot of definitions of the electric displacement and none of them made sense to me, some say it's the electric field in the dielectric, some say it's the density of free charges and some say ...
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Displacement Vector and resultant vector [duplicate]
I am struggling with the concept of displacement. From my understanding displacement can be found for 1D motion along the x-axis as $\Delta x= x_{f}-x_{i}$. For example someone walks $1\,\mathrm{m}$ ...
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What is the difference between |$\frac{ d\vec{r}}{dt}$| and $\frac{d|\vec{r}|}{dt}$? [duplicate]
let $\vec{r}$ be the position vector.
$\frac{d\vec{r}}{dt}$ will be the velocity.
But what is the difference between |$\frac{ d\vec{r}}{dt}$| and $\frac{d|\vec{r}|}{dt}$ ? Do both of them mean the ...
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Does equations of motion work for distance and speed? [closed]
In some books,when solving to find the distance and speed of the object having motion in straight line,the three equation of motion are used.so my question is whether these equation of motion (i.e $v=...
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Acceleration in terms of displacement
I am having problems understanding the derivation of acceleration in terms of displacement. The first step is fine:
$$a(x) = \frac{\mathrm dv(x)}{\mathrm dt}
= \frac{\mathrm dv(x)}{\mathrm dx} \frac{\...
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An adequate way to rewrite the following unitary superoperator
Let us consider a set of superoperators: $X_1, \dots, X_8$ which acts on the density matrix $\rho$ as follows
\begin{equation} \label{eq:algebra} \tag{1}
\begin{array}{ll}
X_{1} \rho = a \rho a^\...
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Is this $x$-$t$ graph possible? Is the distance decreasing over time in this graph?
I have read in a Book:
But I think it is possible as a Negative Velocity and Positive Acceleration:
Reference:
SL Arora Physics Class 11, Pg No. 152.
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What direction should i exactly put for negative displacements?
If I have A....p....B....d....C points
If I am initially on B and walk towards c, it's a positive displacement. Example: BC=10m east and then all of sudden I change my vector and walk to d. Is ...
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DISPLACEMENT OF WATER [duplicate]
Floating objects displace their weight?
what does this statement actually mean?
Does this mean that floating objects displace the amount of water that's equal to their weight and so buoyancy is equal ...
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Displacement of water - Archimedes' principle
Floating objects displace their weight and objects that are completely submerged in water displace their volume. So, my question is that does a floating object displace less water than an immersed ...
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Displacement relation of a progresive wave
I know that the displacement relation of a body in simple harmonic motion (SHM) is given by
$$x(t) = A\cos(\omega t+\phi)$$
Displacement relation of a progressive wave is a similar one:
$$y(x,t) = A\...
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What is displacement time graph for this object which is in $xy$ plane going in sine wave like path from A to B. Also can velocity constant in path?
The path is from A to B in sine wave curve while the displacement is straight line.So how displacement is calculated for graph purpose here
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Is linear momentum times distance any meaningful quantity? $\vec{r} \cdot \vec{p}$ or $pr = mvr$ comparing to $\vec{r} \times \vec{p}$
Angular momentum is$$ L=\vec{r} \times\vec{p}$$
I was wondering if the dot product has any meaning:
$$ ?= \vec{r} \cdot \vec{p}$$
Does it mean anything? It could also be rewritten like $ rp$ or $\...
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Energy and force relation
So in simple machine we apple less force with more displacement to exert same energy as the load need so if energy is related to tiredness i.e. more energy you lose more tired you feel but by applying ...
