All Questions
Tagged with kinematics acceleration
704 questions
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Acceleration of a Bouncing ball when it hits the ground
The conceptual problem I am having difficulty with is something like this:
If a bouncy ball is dropped from some height $h$ and rebounds to a height of $0.75h$ in some time $t$ (for example), what ...
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2
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Kinematics: One dimensional motion
If a particle is moving in one dimension with constant speed, can we say acceleration is zero at all the points?
Answer given in my textbook is yes acceleration is zero.
But I think it can undergo a ...
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Why do these two ways of understanding constant acceleration give different results?
I have a question pertaining to the concept of acceleration and it's formula - Both seem to give me different answers.
I was asked:
A train is moving at a velocity of $20\ \mathrm{m/s}$. It hits ...
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Meaning of normal acceleration?
acceleration means the rate of change in velocity (vector quantity) and the differentiation means to divide a certain quantity into small elements (i.e $dx$) as we do to find the acceleration at any ...
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What is the effect of acceleration due to gravity on horizontal acceleration?
The question is the following:
An object accelerates from rest to $100\,\mathrm{km}$ per hour in $4.0\,\text{seconds}$. What fraction of the acceleration due to gravity is the car's acceleration?
...
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What am I not understanding about this double integration of acceleration to get position?
Brilliant.org has a module on classical mechanics and I'm having difficulty with a mathematical step. They want you to represent position in terms of acceleration and then to solve the double integral ...
user158309
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What is the significance of infinite acceleration in this case? [closed]
the Question is as follows:
Pick the correct statement:
(a) The average speed of a particle in a given time is never less than the magnitude of the average velocity
(b) It is possible ...
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Should not the acceleration acting on the stone being dropped be $a$ as well along with $g$?
the question is:
A stone is released from an elevator going up with an acceleration a. The acceleration of the stone after the release is
(a) a upward
(b) (g-a) upward
(c) (g-a) downward
(d) g ...
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2
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How does instantaneous velocity or acceleration have any other numerical value than 0? [duplicate]
Instantaneous velocity is defined as the limit of average velocity as the time interval ∆t becomes infinitesimally small. Average velocity is defined as the change in position divided by the time ...
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Question about derivation of kinematics equations
Apologies if this has been asked before, but I browsed the sub and couldn't find something specific.
I understand the derivation for one of the equations as follows:
\begin{gather}
\frac{dv}{dt} = a ...
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What causes tangential acceleration
The body moves on a circular path and has both tangential as well as centripetal acceleration.
Friction acts outward as shown in figure. If this friction exceeds mv²/r, then shouldn't the body just ...
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If acceleration $a = v\cdot\frac{\mathrm dv}{\mathrm dx}$ , then why isn't acceleration always zero when velocity is zero? [duplicate]
We know that,
$$\begin{align}
a&=\frac{\mathrm dv}{\mathrm dt}\\[3pt]
&=\frac{\mathrm dv}{\mathrm dx}\cdot\frac{\mathrm dx}{\mathrm dt}\\[3pt]
&=v\cdot~\frac{\mathrm dv}{\mathrm dx}
\end{...
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Four-velocity of an accelerating particle
In the rest frame of a particle, the acceleration four-vector is
$$ \mathbf{a} = (0, g) $$
(see https://users.physics.ox.ac.uk/~smithb/website/coursenotes/rel_A.pdf , Eq.3.51).
By definition
$$ \...
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Accelerometer measures 1g along z-axis
I have an accelerometer which measures 1g along the z axis when resting on a table. I don't understand why this is because the net force on the accelerometer is zero along the z-axis as the force of ...
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Calculate acceleration and lateral G force from GPS coordinates [closed]
I have a data logger that records time (in tenths of seconds), latitude and longitude. I would like to calculate my acceleration and lateral G force based on the collected data. Is someone able to ...
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Is the acceleration of car greater when hitting the accelerator, or the brakes? [closed]
Is acceleration of car greater than when pedal the pushed to the floor or when break pedal is pushed hard? I do understand that the signs would change in either but I am more considered about the ...
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Terminology for time derivative of speed (not velocity)
Is there any standard terminology for the derivative of the magnitude of velocity with respect to time (suitable for use in first-year Calculus)? The word ‘acceleration’, in its technical sense, is ...
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How do you correctly apply $a=v\cdot\text dv/\text ds$? [closed]
I know that $a=v\cdot\text dv/\text ds$ can be deduced by simple algebra and calculus and is correct.
But once I was analyzing the motion of a ball projected straight up in free gravity. If I apply $...
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How much lateral acceleration during cornering is needed to flip a car?
I'm doing my IB HL Math Exploration, where I use a bit of physics. Say I have a car with mass m, center of gravity at height h, and width of 2b, and I am turning a corner, how much centrifugal ...
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Deriving vector equation for average acceleration
How can I derive the vector equation $$\vec{a}_{avg} = \frac{\vec{v}_2-\vec{v}_1}{t_2-t_1} = \frac{\Delta \vec{v}}{\Delta t}$$ for average acceleration?
I know how to derive the average $x$ ...
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What is the difference between uniform velocity and constant velocity? [closed]
I think that uniform velocity implies constant speed but not constant direction. while constant velocity implies constant speed without any changes in direction.
Both tell us that there's no ...
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Problem on circular motion
If a body moves such that its net acceleration always points towards a particular point does this body have constant angular velocity around this point?
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How can I understand if an object stay (zero velocity) or moving with constant velocity (zero acceleration)
I thought a scenario like; lets say I am looking an object and there is nothing except this object. Is there a way to understand that if this object is stay on its position or if object moving with a ...
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Equation of distance and time
How is this equation derived?
$$r = r_0 + ut + at²/2$$
where $r_0$ is the initial position of particle and $r$ is the position of the particle after all the motion it has undergone, $a$ and $t$ ...
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Acceleration and motion can be in different direction?
I'm not getting what acceleration concept is and how it relates to motion and how motion and acceleration can be in different direction? And what's behind the concept of negative and positive ...
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The instant an accelerating object has zero speed, is it speeding up, slowing down, or neither?
This problem is from Khan Academy. Specifically for the blue point circled in red, the answer is that at this blue point, the object is neither speeding up nor slowing down. When I think about the ...
user225790
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Intuition of Distance covered when accelerating [duplicate]
When you're moving at $5$ m/s for $1$ second, you have traveled $5$ m.
When you're moving at $5$ m/s (initial velocity) and you accelerate $2$ m/s for $1$ second, you have traveled $5$ m + $1$ m (...
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Use of direction of downward velocity in equation of motion
[NOTE: I am not asking anyone to solve the question below but to point out where I might be wrong]
Q- A skier jumps from a horizontal track and lands on a steeper track with a launch angle of ∅=11.3°(...
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What is the meaning of transverse acceleration due to work in special relativity?
If we derive the momentum in Special Relativity we get :
$$
\dfrac{\mathrm{d}\boldsymbol{p}}{\mathrm{d}t} = \dfrac{\mathrm{d}m \gamma \boldsymbol{v}}{\mathrm{d}t} = m\dot{\gamma}\boldsymbol{v}+m\...
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Is it possible to estimate linear displacement using accelerometer & gyroscope with the kinematic equations of motion?
I am trying to estimate linear displacement using a 9DOF inertial measurement unit.
My question is:
After correcting the accelerometer readings using the gyroscope, is it possible to apply the ...
rickiepimpim
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Calculating acceleration of an object using $x$, $y$ and $z$ coordinates [closed]
I have x, y and z coordinates for a test I had carried out for a tool. I had an accelerometer installed on the tool and I used two types of motion to move the tool, rotation and translation. Right now ...
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What does a negative acceleration mean? Is the object slowing down, changing direction, or both?
I am confused about such things as negative velocity, acceleration, and displacement and what the negative indicates.
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Is motion smooth? [duplicate]
It's obvious that for every particle velocity is smooth i.e it cannot undergo sudden finite change in its position in infinitisiminal time.
Similarly any particle's velocity cannot undergo a change ...
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Finding tangential and normal velocity from a curve [closed]
How do you find tangential and normal velocity from a curve?
I know how to find dy/dx, but I have no idea how to obtain ut and un and dv/dt.
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Why don't we define time derivative of acceleration? [duplicate]
When we started the study of kinematics we defined position and its change with respect to time. After that we defined time derivative of velocity which gave us acceleration.
These 3 concepts really ...
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Is there centripetal acceleration with velocity of 5 m/s?
So if an object is moving at $5\ \mathrm{m\ s^{-1}}$ in a circle, is it accelerating?
Me and a friend are having a conversation about this.
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Is there a scalar acceleration?
The magnitude of Velocity is simply Speed.
On the other hand, the magnitude of Displacement seems to be a simpler idea than Distance.
And the magnitude of Acceleration is not the change of Speed over ...
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Calculating time taken for acceleration [closed]
about tickertape timer,when we measure the time for a particular object's acceleration, we would take 7 ticks multiply 0.020s(for example), instead of taking 8 ticks. Why do we exclude the other tick, ...
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Speed and tangential acceleration in pendulum motion
Speed is a scalar quantity which corresponds to the magnitude of velocity, so it must always be nonnegative.
In a general 2d motion, the tangential component of acceleration is given by the time ...
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If an object in free-fall is moving upward, the object's velocity is decreasing. Does this mean that the acceleration is -9.8 m/s/s?
I have a problem (that I am not asking you to solve) where it takes $4s$ for an object to travel upward to its maximum height, and we have to determine how far the object travelled. If the ...
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Change of variable in function
Suppose I have a function $h(\theta)$ measuring the height of a piston, with $\theta = \omega t$. I would like to know the vertical acceleration of this piston as $\omega$ changes at the point $\theta ...
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How to decelerate from velocity $v$ to stop time $t$ over distance $d$? [closed]
I'd be grateful for some help with this problem I am trying to solve.
Let's say that I have an object travelling at a velocity $v$. I want that object to come to a halt in time $t$ AND travel exactly ...
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Find the time when tangential acceleration is equal to radial acceleration [closed]
A particle begins to move along a circular path of radius R with a constant magnitude tangential acceleration of $a_t$. After time $t$ it's the centripetal acceleration is equal in magnitude to ...
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How does centripetal acceleration have direction/vector and magnitude while in the formula $v^2=v\cdot v$ is scalar?
$$a_c=v^2/r$$
1. How does centripetal acceleration have direction or vector while in the formula dot product between velocity vector is scalar (as in kinetic energy)? Radius is scalar quantity. What ...
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In the equation for acceleration (with known $v$, $u$ and $s$) why velocity is squared and displacement is multiplied by 2? [closed]
In the following equation $$a = \frac{v^2 − u^2 } {2s} ,$$ where $v$ is the final velocity, $u$ is the initial velocity, and $s$ is displacement. Why is velocity squared and displacement multiplied by ...
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Intuition for formula of tangential component of acceleration in general curvillinear motion
In certain problems of plane motion, the position of the particle P is
defined by its polar coordinates $r$ and $\theta$. It is then convenient to resolve the velocity and acceleration of the particle ...
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Confusion on Horizontal & Vertical Components of a Parabolic Motion
This was a question I found about projectile motion, the question was what's the bike's speed when it took off.
Using $S=ut + 0.5at^2$, the time taken to reach the ground is $0.505 s$, they used ...
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When a body completes one revolution around a circular path will its acceleration be 0?
When a body is moving in a circular motion the acceleration keeps changing, will it be zero when it comes back to the same point it started from(will the average acceleration be 0?)
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Acceleration as the second derivative of displacement function
Let $x$ be displacement as a function of time $t$ and some other physical quantity $k$ such that
$ x = f(t,k) $
Now,
1) Will the acceleration $a$ be $\frac{\partial^2 x}{\partial t^2}$ or $\frac{d^...
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Does the proper four-acceleration $A^{\mu} = (0,0)?$
Let the proper four-position vector $x^{\mu}(\tau) = (0, \tau)$. Differentiating this successively wrt $\tau$ I get the four-velocity $u^{\mu}(\tau) = (0, 1)$ and then the four-acceleration $A^{\mu}(\...
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