Questions tagged [acceleration]
The rate of change of velocity of a body per unit of time.
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Force exerted on vehicle when hitting an object
How can i calculate force that is exerted on a vehicle when it hits an object?
Vehicle speed is 40 km/h, mass is 1500kg
Object is standing still (speed is 0 km/h), object mass is 11kg.
Now this ...
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Does acceleration make you heavier?
I'm looking at this article from Scientific American: https://www.scientificamerican.com/article/star-wars-science-light-speed/#:~:text=Normal%20humans%20can%20withstand%20no,heavier%20blood%20to%...
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Acceleration units [closed]
I often face a questions in test, where e.g. the distance of the particle that moves with the constant acceleration has to be computed, but the acceleration is from some reason not defined in $\frac{m}...
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How can I factor friction into acceleration, given power?
I'm trying to work out an acceleration curve for a vehicle for a simulation, but despite a bunch of research there are a couple of things I still don't understand.
First we have $P = mav$. Assuming ...
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Confusion regarding net acceleration of the bob in the bottommost point of the trajectory of a pendulum?
Here is my analysis from the inertial frame on it:
At the bottom most point,
$g$ acting downwards
$v^2/r$ (centripetal acceleration) acting upwards
So the net acceleration, a = $(v^2/r)-g$ right?
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Are terms tangential acceleration and normal acceleration only used for instantaneous velocity?
Are terms tangential acceleration and normal acceleration only used
for instantaneous velocity?
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Proper acceleration along perpendicular directions
Let's take an object (all times mentioned in this problem are proper times). There is a constant proper acceleration
"$a$" on this object in the x-direction for time $t, 0\leq t \leq \tau$. ...
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Does a simple pendulum have some radial acceleration at its extreme positions where its speed becomes zero?
Suppose we have a simple pendulum swinging between two extreme positions. At the extreme position its speed becomes zero. As per this reason can I say that at extreme positions radial acceleration (v^...
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Why does a centrifuge cause blood to be pushed downwards in the human body?
Good evening all,
I recently watched this YouTube video about a centrifuge by Tom Scott
(https://www.youtube.com/watch?v=DMKcO-T5Y4o). Around the 2:30 mark, it is said that blood will be 'pushed ...
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A 1 kg steel ball is dropped and another is thrown downward with a velocity of 5 ms-1, which will have greater acceleration?
I fail to understand whether if the acceleration will be the same (-10ms-2) or will the 2nd ball have a greater acceleration since I think it's intial velocity would not be 0 unlike the first ball.
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A way of expressing acceleration in general relativity
Using this question:
How can we recover the Newtonian gravitational potential from the metric of general relativity?
I want to formulate my question:
Can the first term of the energy-stress tensor, ...
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About jounce (snap)
About jounce (snap). So change in acceleration is know as jerk, so like this is still imaginable but what is change in jerk, like can you give some real life example where that is happening.
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Question about acceleration
I've been wondering what happens to acceleration when a car reaches the maximum velocity that is capable to produce (let's say 250 km/h). I would assume that the acceleration is decreasing until it ...
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If $F=ma$ does that mean objects traveling at cosntant speeds have no force?
If, say an Elephant (3,500 KG) crashed into me at a constant velocity just under Light Speed(299,792,457m/s, 0m/s^2) would I be subject to no force? If so what would cause me to be hurt in the impact?
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Acceleration perpendicular to constant velocity in special relativity
In newtonian mechanics, if a body is experiences an acceleration that is perpendicular to the direction of motion at all times, it moves in a circle and the magnitude of it's velocity does not change....
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Energy-work theorem and dissipation of energy by an accelerating charge
By the work energy theorem we have that the total energy of a nonrelativistic point charge, $q_0$ of mass $m$, moving in an electric field $\mathbf{E}$ is
$ E = E_k + U_e = \frac{1}{2}mv^2 + q_0V \...
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How can we use Newton's laws in an accelerating frame? [duplicate]
This question is bothering me for a while. As far as I know, newton's laws are valid for any inertial or non-accelerating frame. Then how can we apply newton's law on earth where we are constantly ...
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Velocity addition formula in non-inertial frames
I am a beginner in SR, so the following may seem to be basic. I cannot find any answer in the text books. If there is any, I would appreciate the reference.
The well-known thought experience used to ...
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Deriving length of the rope in bells spaceship paradox
I want to derive the distance between spaceships in Bell's paradox as a function of proper time of the trailing spaceship, in the case of constant proper acceleration of both space ships.
My attempt ...
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What is the electric field between two plates with a hole each (the holes also parallel)?
Suppose you have two charged parallel plates, and an electron on the negative plate. It would move in the electric field to the positive plate. If, however, there was a hole on each of the plates, ...
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Is it correct to say that acceleration slows the frequency of an oscillator?
My question is based on differential aging or differential timekeeping due to, 1) increased speed, and 2) proximity to center of gravitational field. As far as I know, both involve acceleration, and ...
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Gravitational acceleration in my acceleration data (IMU)
I am trying to do gait analysis and remove gravitational acceleration ($9,81 m/s^2$) from my data.
I have used IMU (on the patient's lower back) to record acceleration, angular velocity and roll/pitch/...
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Affine connection on a manifold induced by acceleration field
Suppose I have a classical force field that accelerates all particles, such that the acceleration is a function $A(p, v)$ of position and 4-velocity alone. E.g., Newtonian gravity with a possible &...
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Streamwise Pressure Gradient and Curved Walls
Could someone help me to understand how can a wall generate differents streamwise pressure gradients just by it's curvature? I can understand how it works in cross-flow (perpendicular to the ...
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Can you experience length contraction in an accelerating reference frame?
Imagine I am floating in space some large distance X above a neutron star or high mass object and I am using rocket boosters to stay stationary relative to the object. Assume no other forces acting on ...
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Is the rate with which an object gains speed when it is dropped dependent? [duplicate]
Is the rate with which an object gains speed when it is dropped dependent or independent of the object's weight?
(gravitational force)
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While derivating equations of motion, why do we replace $v$ as $u + at$?
I was learning about the calculus derivations of equations of motion. After the derivation of $v=u + at$, where $v =$ final velocity and $u =$ initial velocity, came the 2nd Equation of motion.
In my ...
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Instantanous and uniform velocity and acceleration
If the mathemical expression of instantanous velocity is $d/t$, what is the mathematical expression of uniform velocity.
If the mathematical expression of instantanous acceleration is $v/t$, what is ...
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Help 3D Rotations! Accelerometer data
I'm trying to find the rotation matrix, R, of my triaxial accelerometers ($XYZ$) and then "derotate" them back to a "default" ($xyz$, with ENU coordinates: $+x$ forwards, $+y$ left,...
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Deriving Rindler Coordinates
I've been trying to understand what Rindler observers are and how do we derive Rindler coordinates. What I've understood so far is that the Rindler observers are a family of observers that satisfy the ...
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Can there be acceleration without work?
Since $W=Fs$, $F=\frac{W}{s}$. When you substitute this in the formula for acceleration, $a=\frac{F}{m}$, you will get that $a=\frac{W}{ms}$. Then, when work equals zero, acceleration will be zero.
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Thrust vector placement for an object affected by gravity to reach a target direction vector
The problem occurred when I tried to calculate the thrust vector angle of a missile for it to fly into a certain direction. Without gravity this would be a really simple problem, but including gravity ...
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Does rate of acceleration change as object gets closer or further to center of a mass?
I learnt that newton's law of universal gravitation F = G(m1m2)/R^2, and thought if the R is distance and determined gravitational strength, why do we use 9.81 as default acceleration of earth's ...
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Flying mosquito problem [duplicate]
Let's say there is a car and its doors and windows are closed. Basically it is a closed space inside. There is a mosquito hovering right in the center of closed space of the car. While doing so the ...
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Why don't we utilize centripetal acceleration for particle accelerators or ion thrusters?
Acceleration of an object in a circle is determined by its radius (r) and speed (v).
Acceleration = (v²)/r
So, acceleration is greater at high speeds and in sharp curves (smaller radius).
Centripetal ...
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Is non-linear acceleration a necessary condition for an object to generate gravitational waves?
I was assuming every object that interferes with the gravitational field creates gravitational waves, and someone pointed out that only objects under acceleration do so. I searched through many sites ...
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The net force received by the bus handle during the acceleration of the bus
Re-post the question by complementing the inaccurate information.
First, I'm just an ordinary person who's interested in physical phenomena and physics. I apologize for not expressing it through ...
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Verification of Accelerometer offset Formula, Offset occurring due to placement of Accelerometer away from centre of rotation in a rigid body [closed]
I have evaluated the Accelerometer offset occurring due to placement of Accelerometer away from the centre of rotation of body. In the below evaluation I am trying to calculate Accelerometer's reading ...
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If current is measured in Coulombs per second, can there be electrical "acceleration"? Coulombs per second squared?
I know I'm making a naïve parallel between current and speed, but why is it naïve? Why doesn't the concept apply?
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Why is Newton's second law seemingly not applicable to a ball rolling down incline plane?
A homework problem asked us to find the acceleration of a ball (pure) rolling down an incline plane without friction. I thought it was simply $a=g \ \sin(\alpha)$ where $a$ is the acceleration of the ...
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Calculation of Accelerometer offset for Placement of Inertial measurement unit away from centre of mass
I am working on a 6DOF IMU that contains a 3-axis accelerometer and a 3-axis gyroscope, I am building a project to
plot the position and orientation of a vehicle/dirt bike in a 3d plane, However the ...
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Acceleration is absolute — is this really true? [closed]
I've looked at the following pages:
Is acceleration an absolute quantity?
Is acceleration frame dependent or absolute?
Is this the reason why acceleration is said absolute?
I don't think any of the ...
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If a body moves along a path (any path, not just circular) with constant speed, is it's tangential acceleration necessarily zero?
If a body moves along a path (any path, not just circular) with constant speed, is it's tangential acceleration necessarily zero?
I could only find general proofs for the case of circular motion and ...
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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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11 years to cross 30,000 light-years?
I solved exercise 6.1 of "Gravitation" by Misner, Thorne and Wheeler and reached the impressive result that it takes only 11 years of proper time to reach the center of the Milky Way (~30,...
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What is the estimated velocity of expansion at the beginning of the Dark Energy era?
Approximately 7.5 billion year ago Dark energy began to accelerate the expansion of the universe. Data has shown us that up until that time the universe was decelerating in its expansion velocity. ...
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Car acceleration limit: friction vs. power
I am currently trying to understand a certain relation between power $P$, velocity $v$ and acceleration $a$.
We are looking at a car driving along a horizontal road and at static friction, and how ...
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Why do we write force = mass × acceleration? [duplicate]
Force is directly proportional to mass and rate of change in velocity i.e., acceleration. So why do we write force as mass times acceleration? I mean why do we multiply mass by acceleration?
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Why $F = m(v_f - v_0)/2$? [closed]
Force is directly proportional to mass and velocity and inversely proportional to time so why don't we write $F=1/t+m+v-v_0$ where $m$ is mass, $v$ is final velocity, and $v_0$ is initial velocity?
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Photon, EM wave
I have been told that an EM wave generate from an acceleration of a charged particle
As the wave propagates away from the charge the field strength of the charge gets weaker, so does the field ...
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