Questions tagged [acceleration]
The rate of change of velocity of a body per unit of time.
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Calculate acceleration (mph/s) of a car from torque (ft⋅lb) and gear ratios
I've checked this question, and while it shows the work I need, it is not the right units, and I need the work to mph/s for acceleration and ft⋅lb for torque.
My questions are:
What are the ...
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2answers
164 views
Is the acceleration of two objects with different temperature same with the same force? [on hold]
$F=ma$ is not the case at relativistic speeds. But what is the total energy including mass which resists against force?
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What forces should I apply in order to make a craft reach a point? [duplicate]
I'd like to find out a strategy for solving the following simplified problem.
A small spherical craft at $t=0$ has a position and velocity vectors $\mathbf{x_0}, \mathbf{v_0}$ in a zero gravity ...
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1answer
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Accelerating a Black Hole
I believe I may have seen this question somewhere with the answer I am looking for, but I can't seem to find it here. If that's the case, then this question may be a duplicate.
I believe I read that ...
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1answer
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Real force analogue names for the coriolis and azimuthal fictitious forces
Consider the following equation (10.10) in Morin's book on classical mechanics, it is meant to provide a correct prediction of the measured acceleration of a particle for someone taking measurements ...
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1answer
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Time dilation of accelerating object vs caught by gravity well
Suppose an object got caught by the immerse gravitational force but at the same time it has zero net force acting on it like suspending above the surface of a planet, not siting on the surface where ...
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2answers
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Roller coaster loop top speed
For a roller coaster loop, if it were perfectly circular, we would have a minimum speed of $v_{min} = \sqrt{gR}$ at the top of the loop where $g=9.8 m/s^2$ and $R$ is the radius of the 'circle'. ...
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Why are the units of angular acceleration the same as that of angular velocity squared?
According to this answer, the units for angular velocity squared are $\mathrm{rad}/s^2$. The units for angular acceleration are also $\mathrm{rad}/s^2$. Why is this the case?
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Why doesn't a braking car move backwards?
The net force on an object is equal to the mass times the acceleration, $F = ma$
When I brake on a (moving) car, the net force is negative, therefore causing the resulting acceleration to also be ...
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Relationship between linear acceleration and angular acceleration shown graphically with velocity vs time graphs [on hold]
So I am writing a lab report and for the life of me I cannot figure out how to display the relationship between the linear acceleration and angular acceleration, both found from graphs of the velocity ...
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Building a cool Fan [closed]
I am building a cool ceiling fan. Its going to have 3 blades with one master blade that is 6 ft. long, its center of rotation will be at 3 ft. obviously. On the to opposite ends of the master blade ...
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2answers
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Does Euler number $e$ have a role in kinematics?
Euler number $e$ is often explained with the example of compound continuous interest.
I was wondering if it could also be illustrated with an example about the displacement of a body (although not an ...
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Does a relationship exist between current, acceleration and charge? [on hold]
I was looking through a study guide question and came across a confusing problem. Here's the setup:
A cross consisting of two wires is first placed in a cartesian coordinate system with the ...
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3answers
728 views
Can we determine an absolute frame of reference taking into account general relativity?
Given that acceleration induces measurable physical effects, would it be correct to say that there should be an absolute inertial frame of reference? I know that one cannot distinguish a priori ...
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1answer
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Imminent car crash, should I brake? [duplicate]
So I am sitting at traffic lights, stationary, in my car.
A drunk driver has crossed over and is about to hit me head on at 40 mph.
I only have enough time to do one thing, hit the brakes or leave ...
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0answers
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Cubic Bezier curve to approximate free-fall
I'm looking to approximate free-fall (on earth) with cubic bezier curves. It seems that the curve depends on the amount of time the object is in free fall, but would be in the form ...
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Clarification of Components of vectors
For finding radius of curvature for a path (eg. Projectile) why do we take component of acceleration ($g$) perpendicular to velocity and not the opposite?
$$\text{radius of curvature} = \frac{\text{...
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Do all accelerating charge emit EM radiation? [duplicate]
A nucleus and an electron attract each other, so if they are to remain apart, the energy of the electron’s movement must balance the energy of attraction. However, the laws of physics had previously ...
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Effective/Apparent Gravity
I am currently learning about non-inertial reference frames in my honors physics class, and I am coming across a concept that I cannot seem to wrap my head around/understand.
After reading this blurb ...
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1answer
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Why mass has no effect on free-fall acceleration? [duplicate]
I learned that mass is a property of objects that specifies how much resistance an object exhibits to accelerate.
So, pushing an object with a greater mass would cause a smaller acceleration than ...
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1answer
109 views
Initial acceleration concerning free fall
I'm in the process of conducting research concerning free fall with air resistence. I'm dropping a beach ball filled with air from certain heigts, while measuring its speed and acceleration during the ...
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4answers
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The change in magnitude of centripetal acceleration
When an object (e.g. racecar) moves around in circles with constant tangential velocity, constant centripetal acceleration is present.
What happens to the centripetal acceleration when the racecar is ...
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2answers
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Can we sum accelerations to get a total acceleration?
I was looking at this question (from the picture below) the other day and I did it by adding the forces in the $x$ direction using Newton's second law and I got the right answer.
My friend on the ...
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2answers
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Confused with derivative and partial derivative
suppose $x=f(t)$ with a constant acceleration.
Then does $\frac{\text d x}{\text d t} = \frac{\partial (x)}{\partial(t)}$ since the position in $x$ only changes with time?
Then the acceleration in ...
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2answers
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Why do accelerating bodies have an event horizon?
I read in a book named "Three Roads to Quantum Gravity" written by Lee Smolin that any accelerating body always have some hidden region of space-time from which light is never able to catch up with ...
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3answers
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Why equation $F = m a$ is not valid in relativistic physics but $F = dp / dt$ is valid?
I read that the equation $$F = m a$$ is not valid in relativistic physics.
Instead $$F = \frac{d }{dt} \frac{mv}{ \sqrt{1- \frac{v^2}{c^2} } }$$ is valid in relativistic physics but why is that?
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1answer
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How does an object in space travelling at constant velocity have a net force of zero acting upon it?
If the definition of balanced forces is "two opposing forces that are equal" and an object with a net force of zero acting upon it means that the forces are balanced on the object, then it should ...
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1answer
39 views
Interpreting derivatives
So we have a function such that the distance moved by a particle (say $s$) is proportional to $sin(Ct)$ where $C$ is a constant.
Now i needed to show that the rate of change of velocity is directly ...
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1answer
37 views
How is the acceleration proportional to the net force over the mass? [closed]
The acceleration is inversely proportional to the mass when the force is constant.
Also, the acceleration is proportional to the force when the mass is constant.
So, how can the acceleration be ...
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1answer
40 views
A question on an elevator and the measurement of $g$?
Imaging a person in an elevator accelarating towards earth with accelaration $a$. At some point the person let a ball fall from his hand. Does the time that ball needs to hit floor equal time that ...
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2answers
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Reason of no reaction force on a person in a lift falling freely under gravity
a person in a lift falling freely under gravity feels weightlessness because the force of reaction between the person and the plane with which he is in contact vanishes. why force of reaction vanishes?...
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2answers
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Two meanings of acceleration in gravitational fields?
Question about General Relativity.
Edit: I've gotten some really good input to help me better phrase my confusion.
I think the heart of my problem is understanding the difference between geodesic ...
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3answers
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The acceleration in Earth's gravity
The acceleration in earth's gravity is $9.807 m/s^2$ at my location. But is this value uniform in the entire earth? For example in the inner core or outer core. What is the acceleration in the center ...
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1answer
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Can a free electron accelerating in a gravitational field absorb photons? [duplicate]
An 'free' electron accelerated in an electromagnetic field can both absorb and emit a photon. What about an election accelerating in a gravitational field?
Edit:
Some users have suggested that the ...
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1answer
116 views
The acceleration of the particles by finite difference [closed]
I would like to approximate the acceleration of a molecular dynamics system.
I'm following an online tutorial to solve a set of equations for molecular dynamics. I can use $F=ma$ to calculate the ...
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1answer
54 views
How would you calculate the force of a hammer hitting an anvil? [duplicate]
If I were to hit an anvil with a hammer (let's say a 1 kg hammer at 1 m/s) how would the force of the impact be calculated?
So, where I'm at with this is that I know the deal with f = mv, so the ...
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1answer
29 views
Particle simulation: understanding mass
I'm trying to understand how mass factors into forces acting on particles in a simulation.
For the sake of argument, imagine a 1-dimensional simulation of a particle, whose position is 0 on the x-...
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0answers
57 views
A person is standing in an elevator, can the elevator and the person have downward acceleration $a> g$? [duplicate]
will the person stick to the ceiling of the elevator?
what will happen if only the person have acceleration a>g?
what will happen if only the elevator have acceleration a>g?
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1answer
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Differentiating linear and non-linear motion
If there is a Person sitting in a vehicle which is moving, how could he find out whether it's in motion and if he figures that out, how does he find out whether it's accelerated or non-accelerated?
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1answer
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Rolling ball accelerating down an incline [closed]
Why rolling ball down an incline or ramp, stops on different spot everytime? I know about friction, gravitational and angular acceleration, but what makes the ball to stop on different place?
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7answers
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How can a particle in circular motion about a fixed point accelerate, if the point doesn't too?
When a particle is performing uniform circular motion attached to a string about a fixed centre, at any instant of time its acceleration is directed towards the centre but the centre has no ...
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1answer
57 views
Are Maxwell's equations valid in a rotating frame?
Maxwell's equations are covariant under Lorentz transformations. Are they covariant under going to a rotating frame and if not how do they look?
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2answers
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Can anyone explain me how do I calculate torque?
For my gate automation project, I estimated the amount of force required (in order to estimate the torque) to pull my gate with a spring balance.
The display on the spring balance read $2 \text{ kg}$. ...
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0answers
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Showing that $4$-velocity and $4$-acceleration are mutually perpendicular in special relativity
The following is said in Landau and Lifshitz
I'm trying to understand how we arrive at formula $7.4$. In my class a different approach was taken if we let $$u^a = \frac{dx^a}{dt'}$$ where $dt' = dt \...
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2answers
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Why is force related to acceleration instead of velocity?
I know $F=ma$, but it's never really made sense to me. Here's an example:
Hypothetical scenario- I push a bowling ball ($m = 4\,\rm kg$) sitting on the floor with $5\,\rm N$ of force. (Assume no ...
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2answers
38 views
Lateral acceleration to angle [closed]
I am doing a 2D simulation in discrete steps of a vehicle.
The vehicle will desire a certain lateral acc. at any given timestep.
So I would like to know the delta angle of the velocity vector after ...
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1answer
40 views
Does buoyant force become less effective as acceleration increases?
Lets say a balloon with a certain amount of buoyant lift has a 2 kg mass strapped to it (including engines) and accelerates enough that it perceives a positive 2.5 g inertial force (2.5g * weight) ...
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1answer
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How does buoyant force react with an acceleration $g$ load?
If a blimp with a certain amount of helium buoyancy accelerated enough to perform, let say, a +2G maneuver, would the buoyant helium force scale along with the weight force?
All the mass particles ...
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2answers
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How is force related to launching objects with a lever?
Suppose we have a class 1 lever, lifting a load of constant mass. All distances remain the same and the only thing that changes is the magnitude of the force applied (effort). Intuitively we know that ...
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3answers
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Mass-energy in relativity
If an object's mass, when measured in its frame of reference (even if that frame is moving), is invariant, then why does it require more and more energy to accelerate it? I can understand this when ...
