Questions tagged [acceleration]
The rate of change of velocity of a body per unit of time.
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How high is the rocket after $t = 30s$ if $\mid \vec{a} \mid = e^{\lambda t}$ [closed]
I'm stuck with the following problem: I'm given the acceleration as a function of time:
$$ \mid \vec{a}(t)\mid = e^{\lambda t}$$ with $\lambda = 0,1s^-1$. I'm asked to find how heigh the rocket is ...
3
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1answer
51 views
Average Velocity ($\vec{\bar{v}}$) Intuition and Analogy for Non-Uniform Acceleration
Background
So I was trying to make as much sense out of kinematics through intuition after having taken my first semester of university physics, and I've stumbled onto a dillema that I can't seem to ...
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5answers
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Is the elevator analogy of the equivalence principle really true?
The equivalence principle as I understand it goes something like this:
Let's suppose you're in a black box in the middle of nowhere in space, and we accelerate this black box in some direction. You'd ...
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0answers
21 views
The motion of a particle through a capacitor
I'm stuck trying to find an equation for the position of a particle travelling through a capacitor, however the capacitor gives an electric field that changes direction the further you get into the ...
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0answers
17 views
How do i find the maximum acceleration of a front wheel driven car? [closed]
Whats the maximum acceleration of a 1600kg car? The static friction μ = 0.8. Front wheel drive.
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2answers
37 views
Is there any reason why $N\ kg^{-1}$ shouldn't be used as the units for acceleration?
When doing a calculation involving a force of $F=1000$ N on a mass of $m=100$ kg we use the formula $a=\frac{F}{m}$
$$a=\frac{F}{m}=\frac{1000\ N}{100\ kg}=10\ N\ kg^{-1}$$
Is there any reason why I ...
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3answers
41 views
Does weight affect the drag force on a falling parachute?
In my physics class we currently have to do research about a motion and preform an experiment and write an essay on it. The idea I had was to drop two parachutes with different areas from the same ...
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2answers
40 views
Is it possible to accelerate the air electrically?
Is it possible to accelerate the air electrically?
There are other techniques such as, for example, compressors where the air can reach supersonic speeds. But is it possible to accelerate air to ...
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0answers
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Two OCR A Level questions on $F=ma$ [closed]
My questions involve the bottom two questions. It's blurry on the left but couldn't do better than that with my scanner, so apologies for that.
Note that this is single maths (not further maths) AS, ...
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1answer
22 views
Speaker on bicycle - would it propel the rider forward?
You strap a super powerful speaker on your back, blast it on max volume. Would it propel you forward?
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4answers
227 views
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Finding accelerations using Instantaneous axis of rotation
Disclaimer: I present a question which is homework-like, However it is simply to demonstrate an example. I only wish to clarify one thing, that is the validity of the IAR in determining the ...
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0answers
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Simplified drone modelling (modelling it as a disc) [closed]
Background: There is this large project, and a part of it requires to simulate movement of quadcopter. The euler-newton equations were decided to be too complicated, and at first it would be better to ...
5
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3answers
295 views
Does tangential acceleration change with radius? [closed]
Do tangential velocity and tangential acceleration change with radius (change of radius on the same object)?
For example consider a spinning disk. Does the equation $$a_t = \alpha R$$ (where $a_t$ ...
1
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3answers
37 views
is the centripetal acceleration have constant direction?
Suppose that we have a circular path which has a radius of $r$ and constant velocity $v$ that is tangent to the circle that the object moving around, I know that centripetal acceleration is expressed ...
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1answer
34 views
Is the initial horizontal velocity of a kicked ball also it's maximum horizontal velocity? [closed]
The horizontal velocity that the ball acquires from the impact of your foot, will this be the maximum velocity, or will there be some horizontal acceleration at first, after which drag will slow down ...
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2answers
83 views
Acceleration as a function of position and time
I know if you have an acceleration as a function of $t$, $a(t)$, to find the velocity you simply integrate $a(t)$ with respect to $t$. Moreover, if the acceleration was a function of position, $a(x)$, ...
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3answers
76 views
Is this formula I derived for net acceleration correct? [closed]
I was thinking about acceleration due to gravity and I thought of deriving a formula that gives the net acceleration due to gravity between two bodies. Now, by net acceleration, I basically mean the ...
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1answer
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How would the air pressure inside the hyper loop affect the acceleration of the cabin?
I would like to ask a question about hyperloop's inner air pressure, how would air pressure inside the semi-vacuum tube affect the acceleration of the cabin? Is there any functions or equations to ...
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2answers
25 views
Using centripetal acceleration to find back the velocity magnitude at $t+dt$
Considering a circular motion with no angular acceleration. How can you find the same magnitude for the velocity vector at different time using the formula $v_{t} = v_0 + a.t$ with vectors?
The ...
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0answers
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Fletcher's trolley apparatus
I can't seem to find any information about who Fletcher was or what his original experiment was ?
Did he first demonstrate the Force versus acceleration experiment using trolleys ?
7
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1answer
397 views
Does Earth's Gravitational pull increase with time?
Gravitational field depends on mass ($g = \frac{GM}{r^2}$) and every year many outside cosmic objects like asteroids or tiny object are hitting earth. So I think may be in a very microscopic amount ...
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2answers
56 views
In the equation: $a = dv/dt$ , is $dt$ the time taken to achieve that instantaneous acceleration?
If you solve for $dt$ from $a = \frac{dv}{dt}$ , is it the time taken to to achieved that instantaneous acceleration?
$a$ : acceleration
$v$ : velocity
$t$ : time
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1answer
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$(v,t)$ Diagram with deceleration and braking
How do you make a $(v,t)$ diagram with braking and deceleration?
When someone for instance brakes and then stops with an uniform acceleration?
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2answers
46 views
For a simple pendulum, why is the centripetal acceleration zero at the apex
Consider the following question.
The answer is $C$.
I am wondering why is there no centripetal force at point R acting towards the center to give it a centripetal acceleration such that the ...
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1answer
39 views
Velocity of particle due to acceleration. Special relativity
I understand how to do transformations of four velocities, acceleration and so on under Lorentz boosts. However after all I have learned in special relativity I still don't know how just an ordinary ...
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1answer
31 views
When the rate of acceleration changes it's sign how does the velocity change?
When the rate of acceleration changes its sign how does the velocity change? When another derivative of distance with respect to time is increased how does it affect factors like displacement and ...
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2answers
38 views
Constant or Uniform Velocity and acceleration
I get confused understanding Constant or uniform Velocity and acceleration when I understand constant speed which means that same distance traveled at same time.
So constant or uniform velocity ...
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2answers
250 views
Alternative expression of acceleration in vector form
Let's imagine a one dimensional case, where a particle is moving with a velocity $v$ and an acceleration $a$. Thus
$$a=\frac{\mathrm dv}{\mathrm dt}\tag{1}$$
Applying the chain rule, equation $(1)$ ...
0
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1answer
43 views
Why do I feel a force from a non-accelerating punch? [duplicate]
If I'm getting punched by a fist that is moving at a constant velocity (let's say $20 \mathrm{m/s}$), I still feel a force that is being applied to my body. However, according to $F=ma$, in order to ...
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2answers
67 views
Does Acceleration due to Gravity take into consideration the centrifugal acceleration due to Earth's spin?
Is the gravitational acceleration we consider only the attraction due to the Earth's gravity or is it that of gravity plus the attraction due to Earth spinning?
We know that earth produces an ...
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1answer
38 views
What is meant with overdamped motion?
I'm learning about Brownian motion. I use the approximation of overdamped motion. I read that the average acceleration is $0$ then, but I don't really understand the concept. So, what does overdamped ...
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2answers
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Why are stationary observers accelerating in the Schwarzschild metric, intuitively?
First, an introduction.
Consider the surface of the Earth (whose mass is $M$): the geometry of the spacetime nearby can be described to a first approximation by the Schwarzschild Metric.
If we wish ...
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1answer
37 views
How do you apply each of Newton's laws to specific scenarios?
The 3 Newton's laws of motion are easy to be understood but examples citing which law caused it are so confusing - say a bullet fired from a gun - many people state it cause is 3rd Law - but I see all ...
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1answer
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The acceleration of gyroscopic precession
If we take the movement of a rotating gyroscope held horizontally at one end with a rope, then the rotational momentum of the gyroscope's spin exists, as well as the rotational momentum caused by ...
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11answers
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What's wrong with this argument that Newton's second law implies all potentials are quadratic?
Newton's second law states:
$$F(\vec{x})=m\vec{\ddot{x}}$$
For $\vec{x}$ scaled by some arbitrary constant $s$, we obtain:
$$F(s\vec{x})=ms\vec{\ddot{x}} \Longleftrightarrow \frac{F(s\vec{x})}{s}=m\...
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4answers
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How can there be acceleration but no velocity at instant of maximum height when object projected upwards? [duplicate]
When we project an object vertically upwards its velocity at maximum height consider to be zero but still, it has acceleration due to gravity i.e $9.8\mathrm{m/s^2}$. But mathematically we know that ...
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1answer
120 views
Is $F=ma$ is true and provable? [closed]
Today, I was watching a video, and the man on the video said that we only "accept" $F=ma$. Then said that no one can prove $F=ma$. But I know we can derive $F=ma$ by momentum with calculus. I am ...
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3answers
103 views
Do electric cars need friction brakes to stop really fast?
If regenerative braking can't stop an electric car fast enough, can't we actively slow it down by applying a reversed voltage to the DC motor?
EDIT: By really fast, I mean in emergency situations ...
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2answers
71 views
Why is the relationship between force and acceleration linear? [duplicate]
When discussing with my children Newton's laws (high school level), I told them (long story short) that one can imagine that since a body on which all forces balance move straight and at constant ...
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1answer
23 views
Travelled distance with accelerated movement knowing terminal velocity and time [closed]
So I have a body which moves straight on a line. The body accelerates from 0 m/s to some velocity V, the acceleration is constant and I know that after T seconds it reaches its final velocity V.
Is ...
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4answers
69 views
Force, Newtons second law
In the book "An Introduction to Mechanics - Second edition" by Kleppner D., Kolenkow R, I came across a paragraph:
pg. 54 , sec 2.5.2(force)
It is worth emphasizing that force is not merely a ...
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2answers
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When does gun barrel length become too long with a constant pressure?
Just struck out of curiosity,
It is a fact that longer gun barrels do increase the acceleration of a projectile, but an infinitely long barrel does not give infinite acceleration. So then, with a ...
2
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1answer
78 views
Motion in helix-shaped wire
A bead of mass $m$ is moving on a vertical axis helix shaped wire of uniform radius $R$ under force of gravity.
Can we apply centripetal force = $(mv^2)/R$ (at any instant when horizontal velocity is ...
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2answers
42 views
How by the fact that mass ratios are identical can we conclude that mass is independent of the source of acceleration? [closed]
I am currently studying Kleppner D., Kolenkow R. - An Introduction to Mechanics, and I stuck at a point where they show that by carrying further rubberband experiment,
By causing motion using ...
3
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5answers
558 views
Can an accelerating body be at rest?
A block of mass $1~\rm kg$ is lying on a table. It is stationary because the gravitational force is balanced by the force from the table. But the body should have an acceleration $g$ and consequently ...
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4answers
926 views
Can I find the acceleration or velocity when my displacement-time graph is discontinuous?
Today, I encountered the problem where I was asked to find the velocity and acceleration from displacement-time graph but the displacement-time graph was discontinuous. So I am unable to find the ...
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2answers
59 views
Why is there no tangential acceleration in uniform circular motion? [duplicate]
I need to know what all is remains constant in uniform circular motion. The tangential SPEED, angular velocity and centripetal acceleration right? Why is there no tangential acceleration in uniform ...
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0answers
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How to measure the gravity component in all the three dimensions using three-axis accelerometer?
I am reading this research paper and trying to understand how the three-axis accelerometer MMA8452Q use in this study to estimate the gravity component for three-axis i.e. $a_x$, $a_y$ and $a_z$.
My ...
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1answer
21 views
Why is the acceleration of the boulder and pallet half that of the truck [closed]
While working on some homework I accidentally seem to have reached a bit of a mental block on this relatively simple problem.
A 5000-lb truck is used to lift a 1000-lb boulder sitting on a 200-lb ...
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1answer
38 views
Movement of blocks stacked together
In the given figure three blocks A, B & C are arranged as shown and a horizontal force $F$ is applied to C. Block A is connected to wall with a horizontal string. The tension in the string is $T$ ...
