Questions tagged [acceleration]
The rate of change of velocity of a body per unit of time.
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Acceleration due to central forces in the Lagrangian
On Wikiversity it states that for central forces:
Wouldn't $\ddot{\vec{r}}_1$ be the same as $\vec{g}$?
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How does a particle move under a constant 4-force?
This question pertains specifically to the case of a constant pure 4-force in special relativity, of the form $\textbf{F} = (f_0, f_x, 0, 0)$, where $f_0 = \frac{γ}c \frac{dE}{dt}$. I understand how ...
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What is tension in cabel of elevator? [on hold]
A block of mass $m$ is kept on the floor of an elevator of mass $M$ and the system is accelerating upward with acceleration $a$. The acceleration due to gravity is $g$.
$F_n$ is Normal force on Block.
...
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3answers
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The normal force in an elevator that's accelerating
I read a problem about a person is standing on a scale in an elevator. When I read the answer, there was an explanation saying that when the acceleration of the elevator goes upward, the normal force ...
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1answer
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Relativistic mass effect
Does relativistic mass phenomena only appear while accelerating or even when the object is travelling at constant velocity (say 90% speed of light)?
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Motion of a particle in a uniform magnetic field [on hold]
The questition states:
A uniform magnetic field exists given by $\mathbf B=b\ \hat k$ . A particle of mass $m$ and charge $q$ is present in magnetic field has an initial velocity $\mathbf v=v\ (\...
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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 ...
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0answers
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Any tips for memorising acceleration in non-cartesian coordinates? [closed]
I need some efficient way to pop up how acceleration in cylindrical/spherical coordinate looks like at the test.
Of course I could derive it on the spot, but it takes too much time (for me) and I ...
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Does all objects really fall with the same acceleration? [duplicate]
I know that acceleration due to gravity is independent of mass :
$$a = \frac{F}{m} = G\frac{M}{r^2}$$
Meaning that a hammer and a feather fall with the same acceleration on the moon.
I am confused, ...
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1answer
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Pulley in a lift [closed]
.
This might be in an easy question.But in the the given figure we write
mg -T = ma
now suppose the lift is accelerating with 2 m/s^2 we get T = m(g-a)~m(6).
now if the lift start accelerating/...
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1answer
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Accelerator on a Turntable [closed]
If a circular particle accelerator were placed on a "frictionless" turntable and then turned on, would it spin opposite to the motion of the accelerating particles?
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Lagrangian of free particle in non-inertial frame
As in Landau & Lifshitz 1st chapter
"If an inertial frame К is moving with an infinitesimal velocity e relative to another inertial frame K', then v' = v+e. Since the equations of motion must ...
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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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1answer
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Could you create a “fast forward” machine using something like an accelerating Ringworld?
If you had a large cylinder in space with people on the inside surface and you started it spinning at a constant acceleration of 1G until it was spinning at near light speed (so the tangential ...
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How to solve the problem of centripetal force with capacitve accerlerometers?
For some months now I am dealing with capacitive acceleration sensors and especially their use in inertial navigation. Meanwhile, I am working on my own inertial navigation system, but I can not find ...
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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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2answers
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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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1answer
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Accelerometer polarity question
Will an accelerometer detect when an object moving it in the -ve x direction and +ve x direction? or will they both produce positive values? (assuming gravity is acting perpendicular to movement, in z ...
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Multiplying acceleration to match speed multiplier to achieve constant time max speed reach
If maximum/desired speed is multiplied by $n_v$, how many times does acceleration need to increase to read speed in the same amount of time?
For example, originally you reach speed $v$ in 1s with ...
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1answer
39 views
Velocity of particle in non-inertial frame [closed]
Can velocity of the free particle remain constant in non-inertial frame as contrast to free particle in an inertial frame?
I know the answer is straightforward yes but taking a different perspective ...
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0answers
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Could apparent horizons of accelerated particles explain dark matter? [closed]
There are some interesting discussions at stackexchange about apparent horizons of accelerated particles (accelerated matter). Relevant links can also be found here SE question 1, SE question 2 SE ...
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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 ...
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0answers
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Does linearly accelerating a swirling liquid slow down its angular motion?
Say you pour some freshly brewed coffee in your favourite mug and give it a nice stir. As you depart for your desk, does the (approx) linear acceleration you apply to the mug slow the coffee's overall ...
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How does the gravitational acceleration on a surface of planet change, if its radius shrinks while retaining the same mass? [closed]
If the radius of the earth were to shrink by $1$%
while its mass remained the same,
then how would the acceleration due to gravity on the earth's surface increase by $2$%?
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7answers
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Why electric potential requires absence of acceleration?
As of 28/05/2019, Electric Potential is defined in Wikipedia in the article with the same name as:
The amount of work needed to move a unit of positive charge from a
reference point to a specific ...
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1answer
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Calculating acceleration of an object using $x$, $y$ and $z$ coordinates
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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0answers
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Finding the acceleration constraint of multiple pulleys
Hello there, I'm trying to understand how Pulleys work. The question asked me to calculate the acceleration constraint that relates the accelerations for each of the masses $m_1, m_2, m_3$. The two ...
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4answers
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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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2answers
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Increasing Mass VS Increasing Force when pushing a Box [closed]
If we assume g=10m/s^2 & negligible friction
The force needed to accelerate that box by 5m/s^2 would be 500N. This is a very basic one.
The confusion came when an force of 250N (the force a 25kg ...
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7answers
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Why doesn't the Earth's acceleration towards the Moon accumulate to create noticeable motion of the earth, towards the moon
I get that Earth's mass is very large, so its acceleration is very tiny. But wouldn't the acceleration accumulate over a period of time and become noticeable?
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Why haven't we yet tried accelerating a space station with people inside to a near light speed? [closed]
Is that something we could do if we use ion or nuclear thrusters?
Wouldn't people in the station reach 0.99993 speed of light in just ...
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1answer
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Boost as a generator of constant acceleration
In Covariant Loop Quantum Gravity by Carlo Rovelli p204, Sec 10.4, there is a paragraph which states
..., a trajectory at constant acceleration is generated by the boost
generator $K_z$ in the ...
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2answers
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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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1answer
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Accelerated frame vs gravity frame
Can accelerated frame change curvature of space as gravity does?
Can there accelerated frame be pure inertial frame?
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Looking for ways to transform time-series data recorded from object movement into equation describing the movement direction of the object
Looking for some time-series data transformation advice!
I want to know what's the best way to transform data of 9-tuples time series data of IMU (Inertia Measurement Unit) sensor, recorded from a ...
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0answers
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Rindler observers are at rest with respect to each other?
I'm studying a chapter about Rindler coordinates right now. In this they say that two Rindler observers at $x = 1/a_1$ and $x= 1/a_2$ will both have speed $v =0$ at $\tau = 0$ compared to the inertial ...
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1answer
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Can satellites stay in orbit when the Earth is being accelerated?
In a TV show I'm watching, the people of Earth have decided to leave the solar system, and take Earth with them, so they've built a large number of powerful rocket engines on one side of the Earth (as ...
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1answer
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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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Would a puddle of spill milk on the elevator floor float when I cut the cable?
Imagine I pour some milk inside the elevator and then I cut the cable to allow the elevator to free fall, does it immediately float or only when the elevator speed has reached 9.81m/s/s? Oh and assume ...
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1answer
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Is the forward acceleration of a parachute equal to its downward acceleration?
I'm writing a small simulation program about parachuting.
I know that the chute will accelerate to it's maximum fall speed at a rate of 9.81 meters per second per second. The forward velocity of the ...
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0answers
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A query on Newton's second law [duplicate]
Upon studying Newton's second law, I noticed that it seems less of a physical law i.e. outcome of some experiment, than something we built upon how WE define mass and force.
The ratio of the masses $...
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1answer
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What part of the energy applied to accelerate electrons radiate and why?
I understand that accelerated electrons will emit radiations, for example in a cyclotron or antenna. However I dont understand why some energy will sort of stay in the electrons and accelerate them, ...
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2answers
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Applying external force on test charge greater than repulsive force of electric field
In the textbook, it is written that only that amount of external force is applied that balances the repulsive force of the electric field without producing acceleration. Without acceleration, is it ...
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0answers
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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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6answers
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Twin paradox - is acceleration relative? [duplicate]
The usual answer to the twin paradox is that the twin who undergoes acceleration is the one who finds the other has aged more, because the trajectory of the 'travelling twin' does not amount to a ...
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What happens when the drag force exceeds the weight of an object falling into earth?
Let's say a meteor is coming towards earth. It's not accelerating, but it does have an initial velocity. This meteor is shaped so it has an insane amount of drag, enough to even exceed its weight (not ...
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1answer
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How does acceleration affect time dilation and length contraction?
I just studied SR and I understand how velocity affects time and length; how do they evolve during the process of reaching a certain velocity?
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1answer
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Normalize accelerometer data based on non-central location
I am trying to "normalize" accelerometer data for a sensor that is not centered on a car. In the image below, you can see how centripetal force changes based on location.
In my case, I only have one ...
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7answers
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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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4answers
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Why the book falls faster than a feather, dropped from the same height? [duplicate]
If I dropped book and feather from same height. Why book falls first, however book has more windage(air resistance), more area(square) than feather?
