All Questions
Tagged with relative-motion special-relativity
148
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What does an observer in a reference frame moving with velocity of light see, when another reference frame with velocity c is launched in opposite? [closed]
Suppose a reference frame is moving with velocity c in +x direction. An observer is there. At any time instance, another reference frame with velocity c is launched in opposite direction, i.e. -x ...
28
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11
answers
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How can any speed be defined as a constant? [duplicate]
We know that the speed of light is a constant, and can therefore be used to calculate many other relative values, but I'm having difficulty understanding how speed can be a constant, seeing as it's ...
0
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1
answer
61
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Momentum conservation of a rocket [closed]
I am trying to solve a relativistic rocket equation. The rocket dumbes fuel $N$ times, in the $-x$ direction, with a mass of $\varepsilon m_0$, where $m_0$ is the rest mass of the rocket. The rocket ...
- 3,122
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Is it possible to determine if you are placed perfectly stationary in outer space?
Many questions and answers that I read are saying that it's not possible to determine absolute stationary position in space. But when I think about it, it seems weird and unlikely.
If you cross-...
- 101
5
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1
answer
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Why do we hold umbrellas upright while walking?
Recently I encountered this (quite interesting) question:
Rain is falling vertically. A man running on the road keeps his umbrella tilted but a man standing on the street keeps his umbrella ...
user249968
7
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6
answers
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Does Special Relativity Imply Multiple Realities?
Thank you for reading. Before you answer my question, I feel I need to let you know that I'm still a beginner in special relativity...so the more thorough the answer, the better. Thank you! Alright, ...
- 3,075
1
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2
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Different apparent brightness of a distant star from a moving frame - an apparent paradox
Consider a stationary star at a distance $L$ from the Earth.
A spaceship at Earth moving with velocity $v$ towards the star will find the star to be at a distance of $\dfrac{L}\gamma$ in its own ...
- 1,421
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2
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Can a magnet deflect a static charge? If not, how do photons work?
A moving magnet is supposed to generate an electric field. That implies that a moving magnet should be able to deflect a static charge. Will the charge be deflected?
If it does not deflect a static ...
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2
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Is the velocity a scalar or a vector in one dimensional Lorentz transformations?
Is the sign of velocity v important in the one dimensional Lorentz transformations?
My question arises because the length contraction and the time dilation effects will work out in exactly the same ...
- 1,421
0
votes
0
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209
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Relativistic trajectory in a constant electric field
I'm trying to write the trajectory ($y^i = y^i(t),\ i \in \{1, 2, 3\},\ y^0 = t$) of a particle seen from an inertial reference frame, ${\cal O\ '}$, that moves along $y^2$ axis with constant speed $(...
- 1,597
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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
2
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4
answers
826
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Why can't we define absolute rest?
If, according to the theory of relativity, as objects gain velocity and approach the speed of light then time for them slows down, why can't we define absolute rest as the inertial frame in which time ...
- 131
2
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1
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666
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Relative velocity from space-time diagram
Consider two frames of reference, with velocities V1 and V2 relative to an initial ground frame. I have made the space-time diagrams for the three frames (Time represented on Y-axis).
As far as I ...
0
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3
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82
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Relative motion with relativity [closed]
In an inertial frame of reference (let's say a car moving with certain constant velocity in which I am sitting)
If I observe the motion of another car through my frame of reference i.e.car, will I be ...
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2
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105
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How can we define event to be proper and improper when there is no absolute frame of reference [duplicate]
Suppose in an empty space two rocketships exists with person A and B of same age inside each. Let A move with velocity c/2 away from B and return. They'll find out that B grew older while A didn't ...
