All Questions
Tagged with kinematics acceleration
704 questions
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How is called the magnitude of acceleration? [duplicate]
According to wikipedia page of velocity:
The scalar absolute value (magnitude) of velocity is called speed
and according to wikipedia page of acceleration:
Accelerations are vector quantities (in ...
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Why is jerk/jolt unintuitive as opposed to acceleration and velocity?
Going from position to velocity to acceleration makes sense. But suddenly acceleration to jerk is hard to grasp. Why is that?
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Kinematic displacement: why not represent higher order rates of change?
I understand that the equation for kinematic displacement is:
$x = v_{0x}t+\frac{1}{2}a_xt^2$
Perhaps my understanding is naive, but it seems like this leaves out higher order rates of change. Why ...
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Average Velocity ($\vec{\bar{v}}$) Intuition and Analogy for Non-Uniform Acceleration
Background
So I was trying to make as much sense out of kinematics through intuition after having taken my first semester of university physics, and I've stumbled onto a dillema that I can't seem to ...
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Does tangential acceleration change with radius? [closed]
Do tangential velocity and tangential acceleration change with radius (change of radius on the same object)?
For example consider a spinning disk. Does the equation $$a_t = \alpha R$$ (where $a_t$ ...
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Using centripetal acceleration to find back the velocity magnitude at $t+dt$
Considering a circular motion with no angular acceleration. How can you find the same magnitude for the velocity vector at different time using the formula $v_{t} = v_0 + a.t$ with vectors?
The ...
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In the equation: $a = dv/dt$ , is $dt$ the time taken to achieve that instantaneous acceleration?
If you solve for $dt$ from $a = \frac{dv}{dt}$ , is it the time taken to to achieved that instantaneous acceleration?
$a$ : acceleration
$v$ : velocity
$t$ : time
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$(v,t)$ Diagram with deceleration and braking
How do you make a $(v,t)$ diagram with braking and deceleration?
When someone for instance brakes and then stops with an uniform acceleration?
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Velocity of particle due to acceleration. Special relativity
I understand how to do transformations of four velocities, acceleration and so on under Lorentz boosts. However after all I have learned in special relativity I still don't know how just an ordinary ...
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Alternative expression of acceleration in vector form
Let's imagine a one dimensional case, where a particle is moving with a velocity $v$ and an acceleration $a$. Thus
$$a=\frac{\mathrm dv}{\mathrm dt}\tag{1}$$
Applying the chain rule, equation $(1)$ ...
user258881
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How can there be acceleration but no velocity at instant of maximum height when object projected upwards? [duplicate]
When we project an object vertically upwards its velocity at maximum height consider to be zero but still, it has acceleration due to gravity i.e $9.8\mathrm{m/s^2}$. But mathematically we know that ...
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Travelled distance with accelerated movement knowing terminal velocity and time [closed]
So I have a body which moves straight on a line. The body accelerates from 0 m/s to some velocity V, the acceleration is constant and I know that after T seconds it reaches its final velocity V.
Is ...
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Motion in helix-shaped wire
A bead of mass $m$ is moving on a vertical axis helix shaped wire of uniform radius $R$ under force of gravity.
Can we apply centripetal force = $(mv^2)/R$ (at any instant when horizontal velocity is ...
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Can I find the acceleration or velocity when my displacement-time graph is discontinuous?
Today, I encountered the problem where I was asked to find the velocity and acceleration from displacement-time graph but the displacement-time graph was discontinuous. So I am unable to find the ...
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Why is there no tangential acceleration in uniform circular motion? [duplicate]
I need to know what all is remains constant in uniform circular motion. The tangential SPEED, angular velocity and centripetal acceleration right? Why is there no tangential acceleration in uniform ...
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Why is the acceleration of the boulder and pallet half that of the truck [closed]
While working on some homework I accidentally seem to have reached a bit of a mental block on this relatively simple problem.
A 5000-lb truck is used to lift a 1000-lb boulder sitting on a 200-lb ...
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Can we calculate centripetal acceleration by using this method $\frac{\mathbf v_2-\mathbf v_1}{T}$?
If we know the angle between two velocity vectors $\mathbf v_1$ and $\mathbf v_2$, and if we know the time $T$ it takes for the velocity to change from $\mathbf v_1$ to $\mathbf v_2$,then is it ...
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Can you use $a=$$\frac{\Delta v}{\Delta t}$ instead of $\frac{dv}{dt}$ to find instantaneous acceleration?
Can you use $\frac{\Delta v}{\Delta t}$ instead of $\frac{dv}{dt}$ to find instantaneous acceleration?
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Is acceleration changing in harmonic motion always
I encountered a question in which particle displacement at an instant was given by $$y=\sin(\omega t-\theta)$$ if differentiate this we get velocity and again differentiating we get acceleration but ...
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Trying to prove that the expression for the radial component of the acceleration is equal to $\mathbf v\cdot \mathbf v/r$
I am trying to prove that the normal component of acceleration of a particle undergoing a curvilinear motion is equal to
$\mathbf v\cdot \mathbf v/r$.
Here $\mathbf v$ is the velocity of the particle ...
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Acceleration vs. time from acceleration vs. distance [closed]
Let's say we have two point bodies, each of mass of 1 unit, 1 unit apart. If we exclude any external forces, gravity starts slowly pulling them towards each other. At some point, the bodies are ...
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Formula for deceleration of a car with transmission disengaged
Related to this answer to a question about the speed of an accelerating car, I'm looking for a formula for the speed of a car decelerating in neutral (with the transmission disengaged, i.e. no torque, ...
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Velocity after applying a force in the vacuum
I’m sorry for so simple question, but I just need to be sure.
I understand, that the changing of the speed occurs only when the force is applied, I understand that if one punch a ball in the free ...
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Determining acceleration in order to meet a space-time-velocity reservation
An Example
A train on a single line track is told to be at position $x_{res}$, at time $t_{res}$, and to be moving at exactly $v_{res}$ when it hits that point. Where $_{res}$ denotes the reservation....
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Integrating acceleration - wrong choice of bounds in textbooks?
I've noticed in my physics textbook (and in a lot of other popular sources), that the process of integrating non-constant acceleration to get to a velocity formula, the integrating bounds imposed on ...
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Direction of average acceleration in circular motion
I know that the instantaneous acceleration is always directed towards the center of the circle.But what about average acceleration.
In the above figure my book says place change in velocity along the ...
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Why is Speed of an object equal to square root of distance traveled multiplied square root of acceleration?
I wanted to find the relationship of the speed of a falling object in a vacuum at g=9.8 m/s2 compared to its distance. I wanted to get time out of the equation. When I plotted the relationship it ...
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Which interval encompasses the greatest deceleration, '$a$ to $b$' or '$c$ to $d$'?
Here we have a vehicle, that accelerates, decelerates suddenly, gains a little more speed and then decelerates until it stops.
[The x axis is for the time in seconds!, t(s) the photo didn't ...
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How to convert acceleration projection to angle?
See a simple webpage here, for an object, if one know the acceleration in three direction $\hat x, \hat y,\hat z$, one could extracted two of the angle of the object between the plane that's normal ...
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When to use what centripetal acceleration? [closed]
There are two equations for it: $a_c = v^2 / r$ and $a_c = \omega^2 / r$.
It seems like they give me different values. I don't know when to use which. Can you explain?
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Conceptual freshman year physics question about acceleration
A particle moves along the x-axis.
When its acceleration is positive,
A. its velocity must be positive
B. it must be speeding up
C. it must be slowing down
D. its velocity must be negative
E. none of ...
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What does the area under an acceleration-displacement curve represent?
Considering the equation where,
$$
\frac {1}{2} \left (v^2_f - v^2_i \right) = \int_0^s ads\,
$$
What does the left-hand side of the equation actually represent? Is there an intuitive explanation ...
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Graph analysis of accelerometer data
I used my mobile accelerometer sensor to collect data from a moving bike where I held it in my hand in a way that the smartphone sensor +Y axis is in the direction of the moving bike always.
This can ...
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If I am decelarating forwards am I accelerating backwards?
If I am in a car and I put the brakes on so that I am slowing down (decelerating) am I then accelerating backwards? e.g. If I am decelerating in this car at -5ms⁻² am I accelerating backwards at 5ms⁻² ...
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How do I calculate final velocity from acceleration, displacement and inital velocity?
How do I calculate the final velocity ($v_f$) given a known constant acceleration ($a$), a known inital and final position ($x_i$ and $x_f$), and a known inital velocity ($v_i$), where $v_i$ can be ...
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Is the car braking time formula $ T = v / (\mu_s \, g) $ valid only for uniformly accelerated motion?
I'm wondering if the car braking time formula is valid only for uniformly accelerated motion.
$$ T = \frac{v} {\mu_s \, g} $$
with $ v $ average speed, $ \mu_s $ static friction coefficient between ...
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Difference between different radial and centripetal accelerations:(Doubt)
In cylindrical coordinates I had derived the acceleration as :
for the first component of acceleration, what is the difference between radial and centripetal ?
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Equations of motion for an object with non-constant acceleration related to its velocity [duplicate]
If I have an object flying through space with an initial velocity $v_0$ and undergoing constant acceleration $a$, then I can easily compute its velocity or displacement at any point in time $t$ using ...
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Graph of distance travelled in $n$th second with time
I was asked to graph the distance travelled in $n$th second by an object with time, taking the object to be at rest initially, and accelerating with a constant acceleration of $1 \, \text{m}/\text{s}^...
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Calculating a free fall vector so its equals to its inverse vector while accounting for gravity
I'm a game developer, and I've been struggling with a kinematics problem in the development process of my current project.
I have some stationary objects that are suddenly affected by gravity after a ...
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Velocity is to speed as acceleration is to ________? [duplicate]
Vectors give both magnitude and direction, whereas scalars can be thought of as magnitude without direction. So, velocity is a vector since it is speed with direction. Similarly, what is the scalar ...
user209860
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What is going on at point A of this velocity-time graph of a bouncing ball?
I was wondering what the ball is doing physically at point A -- is it as soon as the ball hits the floor? If so, what about the section of the graph after point A? Is the ball just coming to a rest?
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What does the dot product of the velocity vector and acceleration vector give me?
I am currently working with some velocity and acceleration vectors and I am a bit unsure about how to interpret the results. Consider the fact that I have 3 points 1.(x1,y1) @ t = 0.0s, 2.(x2,y2) @ t =...
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Related to the information contained in $a = v \frac {dv}{ds}$
While studying kinematics I came to the definition of acceleration which is $a = \frac {dv}{dt}$. But from this equation we can derive that $ a = v \frac {dv}{ds} $ which when I evaluate at $v=0ms^{-1}...
user238497
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Acceleration-time graph for a falling object
I understand that when drawing an acceleration-time graph for a falling object (with initial velocity = 0), the y-intercept should be $9.81ms^{-2}$ and acceleration should end up being $0ms^{-2}$ as ...
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Distance traveled by a particle in $n^{th}$ second
My book states that the distance traveled by a particle thrown upward in the last second is independent of it's initial velocity because the the object travels the same distance as a freely falling ...
user238497
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When the direction of a movement changes, is the object at rest at some time?
The question I asked was disputed amongst XVIIe century physicists (at least before the invention of calculus).
Reference: Spinoza, Principles of Descartes' philosophy ( Part II: Descartes' Physics, ...
user229097
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Having some trouble with acceleration in polar coordinates
So, I solved a question about acceleration in polar coordinates, but most people in my class (Classical Physics, first year at university studying Physics) disagree with my answer. So the question is ...
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Frame of Reference in Kinematics
If we have two frames of reference, say S1 and S2, and the acceleration of a particle as seen from both the frames has equal magnitude, say 4 m/s^2, then shouldn't the frames have no relative ...
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Direction of acceleration vector at the apex of a curve
(Test Your Understanding of Section 3.2)
The question wants me to choose the correct acceleration vector, from the given 9 options where 9th option is zero acceleration.
Ok, first I thought option ...
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