Questions tagged [acceleration]

The rate of change of velocity of a body per unit of time.

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Calculating the power for acceleration of an elevator [duplicate]

An elevator does need some kind of acceleration when it starts to rise up so there has to be s force acting on it. But it surely does not accelerate the whole time so after some distance or time it ...
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Do you really need force to accelerate or move things when there isnt any gravity and air resistance or any other force acting on the object?

Do you really need force to move things around you if there isn't any force acting on the object? For instance if I try to move a box around and there isn't gravity or any force acting on the box, do ...
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A best definition of proper acceleration

In this link of Wikipedia https://en.wikipedia.org/wiki/Hyperbolic_motion_(relativity) there is a definition of proper acceleration: The proper acceleration to a particle is defined as the ...
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Derivation of Coriolis acceleration before vectors got into use

The Coriolis acceleration is known for ages, much before vectors started to be used. Even at the time when Gustave Coriolis was working, vectors were not well established as they are today. Nowadays, ...
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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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Accelerometer outputs vs the real accelerations [duplicate]

TL, DR : the long sentence in bold. I have been reasearching about accelerometers for a while, and I saw many times the following sentence: Accelerometers don't sense gravity, they sense every other ...
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Time taken by bubble to come to surface

Does air bubble take same time to emerge from shallow water and deep water? I think the acceleration due to buoyancy will be the cause.
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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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Variable acceleration relativistic rocket

I was wondering how a realistic fusion-or-something rocket would fly... More specifically, I wonder about the time dilation that would be experienced (say in the classic example of two twins). So, of ...
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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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How would inertia work in an elevator?

If we imagine standing on a scale inside an elevator, the scale will project our weight. As the elevator starts to move downwards we will not start to move downwards immediately; because of inertia we ...
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Is there any easy way to derive acceleration in a circular motion without involving derivatives?

I was given the task to try and teach some physics (mechanics and dynamics mostly) to two young students who don't have any knowledge of math analysis such as limits, derivatives, integrals but they ...
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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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Do accelerated moving electrons radiate electromagnetic energy?

Do accelerated moving electrons radiate electromagnetic energy? Generally speaking, the charge should absorb energy instead of radiating energy in the acceleration stage, and release energy in the ...
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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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Would fast oscillating charged object emit light?

If I were able to mechanically oscillate an electrically charged object at frequencies of 430-580 THz, would the object emit light?
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Uniform Circular Motion vs Change in speed of $x$ & $y$ Components

If you are moving at a set rotational speed the x,y components are constantly accelerating and decelerating (aka simple harmonic motion), this is obvious in order to travel in a circular path. My ...
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How would one calculate velocity with respect to time in Case 2?

Case 1. : The rocket is weightless in space. It's fueled with propellant. It's wet mass is starting mass $m_s$ and dry mass final mass $m_f$. Suppose rocket's initial velociti is 0. The rocket ignites ...
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Can you please explain the statement in the David Morin's Classical Mechanics? [duplicate]

For example, in a hanging massless rope, or in a massless rope hanging over a frictionless pulley, the tension must be the same at all points, because otherwise there would be a net force on at ...
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1answer
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How to find acceleration given the function of the path taken by an object? [closed]

I'm attempting to find how much force a car will experience during cornering. I understand the acceleration acting on the car if it were travelling in a circular path would be $a = v^2/r$. However, ...
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Do objects actually fall at the same rate? [duplicate]

The force of gravity takes the mass of both objects into account. For the sake of argument we are doing the experiment on the moon. The moon + the hammer have a greater combined mass than the moon ...
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1answer
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Force on a particle with uniform velocity

Let's say a particle is moving in a straight with no acceleration in an inertial frame. By Newton's laws we know that the force acting on it must be 0. But my question is, why doesn't uniform velocity ...
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Is it possible that the acceleration of the growth of our universe is driven by the overall gravitational pull of neighboring universes [closed]

I am painfully unequipped when I think about my my knowledge of physics. Still, I am enthralled, as many of us are, by the mysteries and complexity of the universe, both known and unknown. I was ...
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Why bodies with different masses reach gound at the same time in vacuum? [duplicate]

According to Newton's Gravitation Equation $$F=G \dfrac{M\cdot m}{r^2}$$ force of gravity depends upon mass of both objects, and $$F=ma$$ means force is proportional to acceleration. Then why do ...
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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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5answers
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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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Braking power and kinetic energy

I am currently stuck at a part of a problem i set myself. I am trying to create an equation for the stopping distance with respect to the force applied to the braking pads. I currently have two ...
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Angular acceleration about different points on a falling rod

If a rod is allowed to fall gently from its vertical position on a floor with enough friction, it is expected that the point in contact with the floor would be the instantaneous axis of rotation of ...
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Braking systems on cars

I thought of a maths problem for myself to solve, as it seemed like a good problem to try to get my head around. My issue is that I got stuck at the first hurdle. I was reading up about the braking ...
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Acceleration in circular motion

Can motion of a particle be circular if the radial acceleration is zero, but the tangential acceleration is not $0$?
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Is relativity of simultaneity being violated in accelerated frames?

Consider relativity of simultaneity in SR, where 2 observers S and S' are inertial. With the Lorentz transformation $$t=\gamma(t'-vx'/c^2)$$ we can see that the relativity of simultaneity comes from $...
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Explanation on Newton's second law

I have asked a question on I pushing the wall,where the force of me is not zero but as per the formula F=m.a,the force is zero and then I got the answer , it is because here the net force is acting ...
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Force = Mass ⋅ Acceleration [duplicate]

I have a doubt on the formula, $$F=m\cdot a$$ In pushing the wall, as per formula, $F= m\cdot 0=0$ as there is no acceleration hence zero. Therefore force become zero. But we have applied some force ...
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Question about a crate in an accelerating truck and friction force

"A crate is sitting in the center of the back of a flatbed truck. As the truck accelerates to the east, the crate moves with it, not sliding on the bed of the truck. In what direction is the friction ...
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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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1answer
51 views

What is tension in cabel of elevator? [closed]

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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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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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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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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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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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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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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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 ...