All Questions
Tagged with relative-motion acceleration
28
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Accelerating body in a non-inertial frame of reference
If a body is subjected to a force, can I find a non-inertial frame of reference in which the body is not accelerating?
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1
answer
110
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Flying mosquito problem [duplicate]
Let's say there is a car and its doors and windows are closed. Basically it is a closed space inside. There is a mosquito hovering right in the center of closed space of the car. While doing so the ...
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3
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553
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If I accelerate through space, can I say all stars gain kinetic energy?
Suppose I accelerate through empty space. Say all stars are small heavy marbles I can use to do work with by means of their velocity. Say I can let them smash into some generator that turns their ...
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For an airplane moving north from some latitude (say $30^{\circ}N$), why does rotation of the Earth cause an increase in apparent drag?
I'm not able to understand the answer to this example:
Example 10 from the Curtis Orbital Mechanics text book :
An airplane of mass $70 000\ \mathrm{ kg}$ is traveling due north at latitude $30^\circ$...
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11
answers
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What is the essential difference between constant speed and acceleration?
I do know what the difference is but what I am trying to understand is how an object knows its speed is changing and/or how space knows an object is accelerating. The particular thing I am interested ...
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Can we use relative motion if acceleration of two bodies are different?
Suppose, on the $x$-axis, a body $A$ is moving with velocity $v_1$ and acceleration $a_1$, and a second body $B$ is moving with velocity $v_2$ and acceleration $a_2$. $B$ is at a distance of $S$ from $...
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91
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Why does these two masses not have same acceleration? [closed]
Assumptions: No friction , $m_2$=5kg and $z_1$=2kg. $z_2$ is fixed at its place.
Here, there is a mass of $5kg$ on a movable wedge of mass $2kg$. So, my question is that can we say that acceleration ...
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Acceleration and geodesics in General Relativity
Consider this situation:
A) An aeroplane travels a distance from point A to point B which are located on the opposite sides of the Earth. The aeroplane has taken the shortest possible distance to ...
- 159
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Why does the equation for transformation of relative acceleration from one non-inertial system to another involve absolute angular velocities?
It seems that the equation for transforming between two different expressions of the relative acceleration of a vector involves absolute angular velocities, which I find surprising.
Consider two non-...
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419
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If Earth accelerates, what reference frame is its acceleration relative to?
It should be a very fundamental thing, a very simple question. But there's something I want to understand.
We know that when we throw an apple vertically upwards, it experiences a force of gravity ...
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69
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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 ...
- 1,597
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1
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197
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Deriving the equality between the external torque and the rate of change of angular momentum, for a system of particles
I've started working through Analytical Mechanics for Relativity and Quantum Mechanics by Oliver Johns and I'm stuck on deriving a formula.
In the section titled "Change of Angular Momentum", Johns ...
- 103
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3
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191
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If there was but one object in the universe, can it be accelerating or not accelerating?
If there is only a single (material) object in the universe does it still make sense to speak of it as accelerating or not accelerating?
I believe it might be an equivalent question to ask whether it ...
user220934
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300
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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?
2
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1
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424
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To what extent is acceleration relative?
I realize there are answers to my question many places across the internet and many places on this site, but from what I have seen, most of them either involve terms I don't know or assume you can use ...
- 277
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The mechanics of retention of velocity/acceleration when an object is dropped from a moving body
This might seem a stupid question but please help me out because I'm very confused.
We say that when an object is dropped from a moving body (moving with constant acceleration $a$) It has the ...
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A question regarding inertial reference frame
We define a non-inertial reference as a reference frame which is accelerating.
But the question is if it is the reference frame itself what is it accelerating with respect to?
For simplification ...
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6
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How can a particle which is not moving have an acceleration?
Suppose a rod is rotating around a fixed point located at an extreme point of it and there are two points on it. One, somewhere in the middle and the other at the other extreme.Call them $A$ and $B$ ...
- 1,770
11
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How can you accelerate without moving?
I know this question has been asked in other forms, generally regarding the balance of forces. This time I want to focus on motion. I've got a laser accelerometer on my desk. It tells me that I'm ...
user32023
7
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1
answer
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What is my acceleration in my own frame?
This is , I suppose not a good question , but I think I am missing something which confuses me in this question.
So my question is:
Velocity is relative. So suppose a car is moving at a speed $200 \;\...
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Why was it difficult to walk in the same direction the train's acceleration, and easier the other way around?
The other day while I was walking in the same direction that the train was accelerating. Then I came across this question. Please if would answer it, I am very curious to know. But when I walked the ...
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One dimensional motion - Why does a ball fall back in my hands when I throw it up in a moving bus? [duplicate]
Suppose you are moving in a bus and you throw a ball upwards. Why does it always land in your hand and does not fall behind you? The bus is moving with a uniform velocity in a straight direction.
Now ...
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Acceleration of log moving without slipping with/under a plank
So I have this image:
I know how to solve the accompanying physics problem once I have determined the relative accelerations of the logs and the plank. According to my physics textbook, the cm of ...
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745
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Smooth collar sliding down smooth shaft [closed]
For part (a), we find that the acceleration of the collar is $6.94~\mathrm{m/s^2}$. In part (b), we say that the acceleration of B with respect to A is $6.94~\mathrm{m/s^2}$, which makes sense.
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2
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406
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What is the relative acceleration of a projectile fired at in a low gravity vacuum?
This question is to end an old argument.
Given a (space) vehicle with an acceleration of X, and projectile with an acceleration of 2X (rocket, not bullet), what would the relative acceleration of the ...
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416
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Why is speed/position relative but acceleration not? [duplicate]
I think i understand it now, if found this: link
I know that position and speed are relative. There is no such thing as universal coordinates. Then why is acceleration absolute? Is the 3th and 4th ...
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513
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Relative acceleration with pullys
I have tried this question every way I can think but in the equation for particle $L$ $g$ cancels every time. Could someone show me how to do it correctly or tell me what I am doing wrong. Thanks,
...
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Is acceleration relative?
A while back in my Dynamics & Relativity lectures my lecturer mentioned that an object need not be accelerating relative to anything - he said it makes sense for an object to just be accelerating. ...
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