Questions tagged [acceleration]
The rate of change of velocity of a body per unit of time.
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Having some trouble with acceleration in polar coordinates
So, I solved a question about acceleration in polar coordinates, but most people in my class (Classical Physics, first year at university studying Physics) disagree with my answer. So the question is ...
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1answer
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Acceleration of speed of light
If we consider the equation "$E=mc^2$" and if we differentiate the equation with respect to time, e.g.
$$\frac{\mathrm dE}{\mathrm dt}=m\frac{\mathrm dc^2}{\mathrm dt},$$
we will get after ...
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Finding acceleration from drag force/initial velocity in terms of terminal velocity
A ball is thrown horizontally with an initial velocity of half of its terminal velocity. What was its initial acceleration?
I understand that being thrown at half terminal velocity means a drag ...
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How to find acceleration with angles included? [on hold]
[![enter preformatted text here][1]][1]How do I find acceleration of an object if I have force, mass, friction, and there is 2 given angles (object and force)? I ...
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Average acceleration [on hold]
The space shuttle Discovery has made 30 flights. The space shuttle is approximately 37 meters long and has a wing width of 24 meters. The three main engines of the space shuttle are used when ...
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Frame of Reference in Kinematics
If we have two frames of reference, say S1 and S2, and the acceleration of a particle as seen from both the frames has equal magnitude, say 4 m/s^2, then shouldn't the frames have no relative ...
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5answers
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Formulation of Newton's second law
Assuming a constant mass, which would be best way of expressing Newton's second law? $F=ma$ or $a=\frac{F}{m}$? The most common way is the first one, but I feel more comfortable explaining it the ...
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1answer
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Why don't all the bodies accelerate as all of them are brought into motion through a force?
Like in a Projectile, why isn't there an acceleration in the horizontal direction? I've seen things like there isn't any force acting (in the horizontal direction) but for the body to move there must ...
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1answer
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Direction of acceleration vector at the apex of a curve
(Test Your Understanding of Section 3.2)
The question wants me to choose the correct acceleration vector, from the given 9 options where 9th option is zero acceleration.
Ok, first I thought option ...
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2answers
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Moving objects and gravitational radiation
I have read that GR predicts that moving, massive objects emit some of their energy as gravitational waves. In reality, the energy loss is negligible and undetectable, but in some systems, like PSR ...
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What does the total acceleration from a linear accelerometer tell me?
Im trying to measure the acceleration of a heavy bag in martial arts when it is hit. If I am using an linear accelerometer that is strapped to the heavy bag and tells me x, y, z and the total values ...
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1answer
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Calculating Acceleration To a Predetermined Point [closed]
I've been struggling to find a solid solution for a problem I'm having.
I have an object in 2D space moving at some initial velocity, from some initial point to some final point, over a determined ...
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2answers
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${}$ Kinematics: One dimensional motion [closed]
Above is the speed-time graph of a particle in motion along a constant positive direction, as per my textbook accelration in the interval 3 is positive. But I think acceleration in the interval 3 is ...
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2answers
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Acceleration of a Bouncing ball when it hits the ground
The conceptual problem I am having difficulty with is something like this:
If a bouncy ball is dropped from some height $h$ and rebounds to a height of $0.75h$ in some time $t$ (for example), what ...
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2answers
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Kinematics: One dimensional motion
If a particle is moving in one dimension with constant speed, can we say acceleration is zero at all the points?
Answer given in my textbook is yes acceleration is zero.
But I think it can undergo a ...
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1answer
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Lagrangian form of acceleration
Reading the Wikipedia article on Lagrangian mechanics I have problems to understand one basic proposition in the motivation of Euler-Lagrange equation.
The article says:
For me is unclear how the ...
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Why do these two ways of understanding constant acceleration give different results?
I have a question pertaining to the concept of acceleration and it's formula - Both seem to give me different answers.
I was asked:
A train is moving at a velocity of $20\ \mathrm{m/s}$. It hits ...
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1answer
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Why is it impossible to start or stop an object instantaneously? In what ways can a non-accelerating object move? [closed]
Why is it impossible to start or stop an object instantaneously? In what ways can a non-accelerating object move?
I think this has to do something with inertia, but I am not exactly sure I fully ...
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4answers
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Why does body with continuous speed generate force?
So... sorry if the question seems a bit stupid, but it's been nagging me all day and I couldn't find an answer on the net. It goes like this: If a body, say, a car is moving with constant speed. This ...
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2answers
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Does a relaxing electron really accelerate?
This is not a duplicate. I am not asking about quantum leaps or quantum jumps or whether the transition is instantaneous (yes I asked that question before here Do electrons really perform ...
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1answer
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Meaning of normal acceleration?
acceleration means the rate of change in velocity (vector quantity) and the differentiation means to divide a certain quantity into small elements (i.e $dx$) as we do to find the acceleration at any ...
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How does this toilet lid work?
After further reflection after closing the lid on my toilet, I noticed it exhibited a behaviour that I can't explain. When you let the lid fall, it falls at a constant speed regardless of its angle. ...
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3answers
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What is the effect of acceleration due to gravity on horizontal acceleration?
The question is the following:
An object accelerates from rest to $100\,\mathrm{km}$ per hour in $4.0\,\text{seconds}$. What fraction of the acceleration due to gravity is the car's acceleration?
...
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2answers
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How can we know direction of blocks in pulley systems?
How can we find the direction of acceleration in pulley systems so that we can write equation of motion for different parts of the pulley system. Do we have to assume acceleration in some particular ...
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3answers
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Are electromagnetic waves only caused by accelerating charges?
Like the title says, are electromagnetic waves only caused by accelerating charges? Are there any other methods for the generation of photons?
If electromagnetic waves are ONLY able to be created by ...
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Acceleration of a falling object as it hits the ground
I am pretty new to physics so forgive me if this seems like a really dumb question.
My Physics I teacher is having us develop a solution to the question:
You drop your laptop; what is its ...
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What causes the block to move horizontally on a FIXED wedge
Questions:
For a block kept on a FRICTIONLESS FIXED INCLINE the acceleration down the plane is g*sin(A) (A is the angle of inclination) this acceleration can be further said to have components in the ...
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2answers
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What does the first postulate of Special Relativity mean?
Physical laws are invariant regardless. It can be an inertial frame and also a non inertial frame. Now it is the case you cannot do any experiment in an inertial frame of reference to test if you are ...
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1answer
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How is do you say the “standard acceleration of gravity, $g=9.80 m/s^2$” in words? [closed]
How is do you say 9.80 m/s^2 in words? (I Don't get if only "the second" is squared or the whole thing is squared or just the m/s is squared)
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3answers
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Find velocity from acceleration equation [closed]
Suppose the acceleration of a particle is a function of $x$, where
$$a(x) = (2.2 s^{-2})x$$
(a) If the velocity is zero when x = 1.0 m, what is the speed when x = 3.4 m?
(b) How long does it take ...
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What am I not understanding about this double integration of acceleration to get position?
Brilliant.org has a module on classical mechanics and I'm having difficulty with a mathematical step. They want you to represent position in terms of acceleration and then to solve the double integral ...
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2answers
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Discussion - Why will an object move downwards inside a rocket moving upwards?
Suppose a rocket is launched upwards , and an object (say on the top of the rocket, inside the rocket) is at rest.
If i'm correct , as soon as the rocket starts moving upwards , the object would ...
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2answers
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Need of describing the term acceleration [duplicate]
What is the need of acceleration when we have velocity
As I think velocity as 1m/s means 1m covered in 1s and 1m/s^2 means 1m covered in 1s per 1s this statement creates confusion when it comes to ...
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2answers
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What is the need of acceleration? [closed]
As we can usually predict the various forces that a body might be undergoing based on its position and its velocity.Hence what is the need of acceleration?
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1answer
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Why are you accelerating yet remaining at a constant speed while going around a curve? [duplicate]
We have to write a rap in physics, and it has to answer a prompt he gave us on this packet. The prompt for the verse I am writing is:
Pretend you are driving a car on the freeway going 65 mph. The ...
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Why do accelerations due to gravity and external forces get added during upward motion? [duplicate]
Suppose there is guy in an elevator, who has a mass of 100kg. The elevator is ascending with an acceleration of $10m/s^2$.
What would be the apparent weight of the guy?
Now, my resources tell me ...
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How do you calculate how heavy you feel from negative g forces? [duplicate]
My physics tacher told me that to calculate the weight that you feel from negative g forces you have to devide your mass by the negative g force, but then my friend told me that it did't make sense ...
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1answer
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How much weight do you feel during negative g-forces?
My physics teacher told me and some other students that when you experience negative g-forces, your weight equals: $$\frac{mass}{g_{force}}$$
So when the g-forces equal -4 g your mass will be:
$$\...
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1answer
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Measuring acceleration due to gravity in the lab
I am measuring the acceleration due to gravity in the lab with an electromagnet apparatus.
My textbook says to take the average time for a number of falls (keeping the height constant of course).
...
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3answers
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Time dilation calculation in the relativistic rocket
Rindler coordinates are useful for describing objects moving at constant acceleration:
\begin{equation}
\mathbf{x} = \begin{pmatrix}
t \\ x
\end{pmatrix} = \begin{pmatrix} \xi\sinh [\alpha \zeta] \\ \...
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1answer
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Two objects undergoing proper acceleration
Is there an inertial frame ($x'$, $t'$) in which two objects undergoing proper acceleration in the positive x-direction (e.g. starting from rest at $t=0$ from $x=0$ and $x=L$) where the two objects ...
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1answer
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Solution to object with proper acceleration [closed]
An object undergoing constant proper acceleration has the 4-vectors
describing their location obey
$$\frac{d\vec r }{d\tau }\cdot \frac{d\vec r}{d\tau }=-1$$, $$\frac{d^2\vec r}{d\tau ^2}\cdot \frac{d^...
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1answer
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Cylinder rolling down an incline in a vacuum
Say you set up an experiment with an inclined plane, and a cylinder rolling down the plane. Let's also let the experiment happen in a vacuum, such that there is no air friction.
However, let there be ...
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1answer
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Feynman Lectures on Physics: Vol 1, 11-6: acceleration vector
I’m trying to get through 11-6 section of Feynman’s Lectures on Physics, Vol 1, particularly explanation of acceleration vector calculation in his example:
It’s clear that acceleration ...
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1answer
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Unreachable relavistic particle in accelarated motion
Let's say I have a particle in a uniformly acclerated motion such that
$$
a_\mu a^\mu = -g^2, \quad g > 0\ {\rm and\ constant} \tag1
$$
I want to prove that any signal coming from a apace-time ...
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1answer
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What is the significance of infinite acceleration in this case? [closed]
the Question is as follows:
Pick the correct statement:
(a) The average speed of a particle in a given time is never less than the magnitude of the average velocity
(b) It is possible ...
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2answers
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Why doesn't an accelerating body on collision come to rest immediately? [closed]
Let us consider two bodies (A and B) lying on a surface at a certain distance from each other. Let A be accelerating to the right, towards B and hence, the force experienced by A be F. When A collides ...
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1answer
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Weight in an elevator accelerating downwards with $2g$
I am aware of the classical apparent weight physics but I am confused about what happens when elevator falls with greater acceleration than g say two g or something.if I calculate the normal force it ...
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3answers
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Should not the acceleration acting on the stone being dropped be $a$ as well along with $g$?
the question is:
A stone is released from an elevator going up with an acceleration a. The acceleration of the stone after the release is
(a) a upward
(b) (g-a) upward
(c) (g-a) ...
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0answers
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Adjusting Newton's laws with relativity concepts
I break my question into three parts, with increasing "guessing status". Please tell me which of them (is any) is correct.
Suppose I am an observer in an inertial reference frame, away from all other ...
