Questions tagged [acceleration]
The rate of change of velocity of a body per unit of time.
2,027
questions
-2
votes
0answers
29 views
Finding velocity and position of $a (t) = −ω^2 (C_1 \cos θ + C_2 \sin θ)$ [closed]
I'm stuck with this:
A type of movement found in many phenomena in the
Physics can be modeled through a particle that is subject to a
linear acceleration (motion in one dimension) given by the ...
-1
votes
3answers
102 views
Is this the reason why acceleration isn't change in velocity per unit distance?
I believe that the reason acceleration isn't measured as change in per unit distance but instead is measured as change in per unit time is because of the following reason :
Time is not geometrical. It ...
1
vote
1answer
41 views
Need Help Understanding Why $\Delta \vec{v}$ is Perpendicular to $\vec{v}$
I am confused about the statement of how vector $\Delta \vec{v}$ is perpendicular to vector. I highlighted the statement in pink. I ended up copying the image of the right vector $\vec{v}$ in the ...
0
votes
7answers
94 views
Vertical motion of an object
We define acceleration as $-9.8\frac{m}{s^2}$ for an object that is thrown upwards due to gravity. My question is when the object reaches maximum height at the point where it is about to turn around ...
0
votes
1answer
71 views
Question about uniform acceleration [closed]
I am studying for my university test and I have this question and it goes like this.
A marble that starts from rest, slides down a slope of $30^\circ$. If there's no friction, what will be the speed ...
1
vote
1answer
28 views
What if inertial and gravitational mass were different?
It's well known and heavily documented that gravitational and inertial mass are identical.
This has been experimentally tested to many digits of precision.
But nothing I've seen ever describes how ...
0
votes
2answers
43 views
If an elevator and its shaft were weighted, would they weight less as the elevator goes up?
I have a question that would probably be easy for you.
If we could put an elevator together with its shaft on a scale and have its motor pull it up, lets say for 50 floors.
will the reading on the ...
0
votes
1answer
38 views
How to determine the correct time using quadratic functions if there are multiple “correct” roots exist in a 3D system? [closed]
Time can be calculated from a modified kinematics quadratic formula using the initial velocity, displacement, and acceleration. However, the acceleration vector isn't limited to 1 axis.
When applying ...
0
votes
2answers
52 views
Newton's 3rd law and normal force
There is something I hope you can help me understand...
According to my physics course, when I stand on the surface of earth, the normal force prevents me from "falling down" because it's ...
1
vote
3answers
94 views
Suppose there is a vector $\vec v$ which is a function of time, then will $\dfrac{d}{dt}|\vec v|$ be a vector quantity or a scalar quantity?
Suppose there is a vector $\vec v$ which is a function of time, then will $\dfrac{d}{dt}|\vec v|$ be a vector quantity or a scalar quantity?
I think it should be scalar because, let's assume $\vec v=...
2
votes
2answers
84 views
What does not accelerate?
According to special (& galilean) relativity, there is no difference between constant movement or not moving at all but it is possible to detect acceleration and rotation is acceleration.
The ...
3
votes
2answers
57 views
How to gradually calculate deceleration to reach velocity = 0
I've tried to remember everything I could thats related to physics I've learned in school and college, but I'm failing. I'm currently trying to develop the physics of my own game (I could instead use ...
0
votes
1answer
32 views
How to read an acceleration-time graph? [closed]
The acceleration-time graph for the motion of a particle that starts with a positive velocity is shown below:
It is a multiple choice question and I am asked to select the false statement which I did ...
0
votes
1answer
25 views
Doppler effect observed on pendulums
I wanted to investigate the doppler effect on pendulums and set up an experiment where:
The bob of a pendulum is a speaker which emits a specific sound frequency.
Directly underneath the lowest point ...
2
votes
2answers
135 views
A string between two accelerating spaceships vs two falling spaceships
According to Bell's spaceship paradox, a string between two uniformly accelerating spaceships will break. According to the equivalence principle, a string between two spaceships freely falling in a ...
1
vote
1answer
19 views
Help with finding speed and coordinates [closed]
Can you please help me with this I'm stuck?
A particle starts from rest at $t=0$ at the origin and moves in the XY plane with a constant acceleration of $a=( 2i+4j)\ \mathrm{m/sec^2}$
After a time of $...
5
votes
4answers
1k views
How is the acceleration of all the blocks same in this problem? [closed]
In solution of this problem the acceleration of all the blocks is taken same as $a$ . But won't the acceleration of Block $A$ and $B$ be different and the acceleration of Block $C$ would be the sum of ...
0
votes
2answers
71 views
What is the analog of the equation $\frac{d^2\vec{r}(t)}{dt^2}=\frac{\vec{r}(t)}{\left|\vec{r}(t)\right|}f(\vec{r}(t))$ in Quantum Mechanics?
In Newtonian Physics the general equation for the acceleration when there is a central force is $$\frac{d^2\vec{r}(t)}{dt^2}=\frac{1}{m}\frac{\vec{r}(t)}{\left|\vec{r}(t)\right|}f(\vec{r}(t))$$ with $...
-1
votes
2answers
92 views
Are uniform acceleration and uniform motion the same? [closed]
Found this question from my textbook. Any answers are appreciated, thanks. :D
1
vote
2answers
121 views
Force creates the motion or Motion creates the force?
Motion Creates Force ?:
When you move your hand (to push a box for example), it creates a force.
When electron moves through a wire it creates electrical force.
Or Force Creates Motion ?:
Gravity ...
0
votes
5answers
199 views
Version of the twin paradox without accelerations
The main argument used to solve the twin paradox is based on the accelerations and decelerations of the observer considered to be in motion. In the twin paradox of the version described here, ...
1
vote
2answers
104 views
Velocity and acceleration in special relativity
I would like to compute what the constant acceleration trajectories are in the Minkowski spacetime $(t, x)$ with $d\tau^2 = dt^2 - dx^2$. So given some trajectory $x(t)$ I know the velocity vector is ...
0
votes
2answers
94 views
Derivation of the acceleration of an observer through direct use of the Lorentz transformation
In his paper "Uniformly accelerated reference frames in Special Relativity", E. Desloge describes the acceleration of an accelerated observer through what he refers to as a direct ...
0
votes
1answer
22 views
Galileo's treatment of uniformly accelerated motion
Galileo asserts that if a body accelerates uniformly, its velocity increases as the even integers ($1,2,3,4$ etc.) and therefore, the distances passed by the body in equal times increase as the odd ...
0
votes
1answer
39 views
Why does accelerating break the synchrony between two clocks?
The standard method for synchronizing two clocks is to exchange light signals between the them and ensure the satisfy the relation $t_A' - t_B = t_B - t_A$. This method works because both clocks can ...
4
votes
0answers
25 views
Estimating the displacement/force of a string (eg. guitar, piano) being struck by a mass (eg. by hammer or plectrum) at a given initial velocity
I have created a string audio synthesizer (eg. guitar, piano) based on physical modeling. It incorporates modeling for all the major phenomena that characterize a string. This includes things like ...
5
votes
4answers
380 views
General Relativity: Definition of Locally Inertial Frame
The Einstein Equivalence Principle states that in a sufficiently small frame of reference is impossible to know if we are into a gravitational field or not. Equivalently we cannot say if we are in an ...
3
votes
3answers
107 views
$F = ma$ and instantaneous force
I'm new to physics and trying to understand Newton's second law $F = ma$ but I don't think I'm grasping the concept of force very well. I've read other questions and answers on this law and it is my ...
1
vote
1answer
92 views
Absolute Acceleration in a Train
How would you calculate the total acceleration of a human body that is just starting to walk in the train against the direction of the train, who is also accelerating? Actually I want to have an ...
-1
votes
3answers
78 views
Acceleration of a massless body [duplicate]
Let's say we have a massless body connected to 2 strings. Now lets pull the body with a force $F$. As the body is massless tension in both strings will be equal. Let that be $T$. Now we know that $$F-...
4
votes
3answers
114 views
What would prevent object from experiencing an infinitely powerful jerk in an instant?
Unlike speed which is capped for anything with rest mass at speed of light in a vacuum, what would prevent an object to undergo infinite acceleration in an instant? I assume in theory if we can apply ...
0
votes
2answers
130 views
What kind of motion does a quadratic position time graph represent? [closed]
When I make a function to represent an object's position at intervals of two seconds, and it is parabolic, for example $f(x)=\dfrac{5x^2}{2}$ with the following points:
$ \text{seconds} \ \ \text{...
0
votes
0answers
35 views
Lorentz Transformation and Rindler Coordinates
So I saw in a book the following derivation of the Rindler Coordinates: Considering the rest frame as $S$ and an instantaneous rest frame $S'$ under acceleration $\alpha$. The observer in $S'$ is at ...
1
vote
3answers
129 views
Why do we fall towards earth and not hover during free fall as per General relativity? [duplicate]
So this is what I understand from General Theory of Relativity:
A body freely falling towards earth's surface would be in an inertial frame of reference (air removed) with zero net force acting on it. ...
1
vote
3answers
99 views
Why don't we consider the change in $g$ while determining the acceleration of a free falling object?
$$F=mg$$
Why is the acceleration constant? Shouldn't it change as it is thrown upward as the distance from the earth increases.I know the effects would be very negligible but is there any equation to ...
1
vote
1answer
48 views
Tolerability of extremely high acceleration for an extremely short period?
I've been wondering about this for a while. So let's assume a ship accelerates at 1 million G for an extremely short period of time, such that its total velocity change was (say) 1cm/s. Would the ship ...
-2
votes
6answers
99 views
How is acceleration calculated when only the direction of velocity changes and the magnitude remains the same? [duplicate]
How is acceleration calculated when only the direction changes and the magnitude remains the same?
Guys, I know that my previous examples didn’t make sense and I’m sorry because I’m totally new to ...
1
vote
1answer
20 views
Calculating the position of an object given object's initial position and velocity influenced by given acceleration vectors
The red circle is being pulled by two gravity points. Assume that the red circle has a given position (x,y) and a given velocity (vx, vy).
I need to calculate the velocity and position of the red ...
0
votes
1answer
63 views
Can a constant force cause variable acceleration? [closed]
Can a constant force cause variable acceleration?
I think that the answer is no.
How can a force cause variable acceleration?
0
votes
0answers
33 views
Why don't we use vector sign for quantities in 1D motion? [duplicate]
My school textbook says that we don't need to use unit vectors (i ,j,k) to represent the direction of vectors in 1D motion as + and - sign indicate direction. But that is creating a lot of confusion ...
1
vote
1answer
17 views
Is it correct in projectile motion tangential and normal acceleration changes, whereas the net acceleration remains constant ($g$)?
If we think of projectile motion as a general curvilinear motion, the magnitude of tangential acceleration is given by $g sinθ$, and magnitude of normal acceleration is given by $g cosθ$, where $θ$ is ...
14
votes
3answers
3k views
What force accelerates a liquid moving in a narrowing pipe?
Say there is a liquid which behaves like an incompressible fluid and is flowing steadily through a pipe which is moving from a cross section of area $A_1$ to the cross section of area $A_2$, where $...
0
votes
3answers
195 views
Are acceleration and velocity simultaneous? [closed]
I would think yes because, if a rope tied to a swinging rock breaks, the rock flies off in the direction that is perpendicular to the direction of the last instant of the acceleration. The ...
-1
votes
3answers
46 views
Ambiguity of Pseudo Forces [closed]
Suppose we have an observer standing still in an inertial frame of reference. We will consider a scenario where there are no real forces acting on them in the inertial frame.
If we define a non-...
1
vote
1answer
32 views
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 ...
2
votes
0answers
91 views
Gravitational waves emitted by accelerating rocket
What is the gravitational wave luminosity of a rocket with mass $m$ (kg) accelerating at $\Delta v$ (m/s$^2$)? Intuitively, I expect the luminosity (in Watt) to depend on the mass and acceleration. ...
1
vote
1answer
38 views
Strong gravitational field equivalent to accelerated frame
I have recently learned about the equivalence principle and what it says is that( If I have understood it properly) the trajectory of the particles will be the same irrespective of the properties of ...
1
vote
3answers
61 views
Are falling objects harder to push compared to objects at rest
While an object is still in the air falling under the influence of gravity, does it take greater force to push or steer it to the side compared to when the object is in a state of rest?
0
votes
1answer
34 views
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?
0
votes
1answer
30 views
Force between a second and third body is such that they are rigidly bound together to form a composite body
I am currently studying the textbook Classical Mechanics, fifth edition, by Kibble and Berkshire.
In classical mechanics, we have that
$$m_1 \mathbf{a}_1 + m_2 \mathbf{a}_2 + m_3 \mathbf{a}_3 = \...
