The reference-frame tag has no wiki summary.
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Faster than light due to reference position [duplicate]
Possible Duplicate:
Travelling faster than the speed of light
Please try to follow and clarify me I've been curious about this for a long time as it seems a bit paradox due to the rule that ...
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Motions in Non-inertial reference frames? Reference -request
The course 0.2061 in Aalto University covers motion in non-inertial-reference frame but without examples and without references (examples are outlined only in lectures but I find them very hard to ...
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613 views
When does not Newton's 3rd law apply?
Is Newton's 3rd law valid in non-inertial frames?
If so, then are there other cases for which Newton's 3rd law is not applicable?
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Time slowing down problem
When someone moves, time slows down for him. Let, a man standing still and another moving very very very fast, this happens for an hour (as measured by the standing man). Time has moved slower for the ...
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1answer
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Calculating velocities using Reference frames
Suppose an object A is traveling at a velocity of 100 m/s, and another object B is traveling at 105 m/s. With both the objects traveling through the same direction, taking A as a reference frame, the ...
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1answer
334 views
Two trains at the speed of light [closed]
Okay. Two trains travelling towards each other at the speed of light. So, from one train (let's call it train A), the other is moving towards it at the speed of light. The other train shines a torch. ...
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2answers
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A relative time dilation paradox.
Let us assume that there are two astronauts A and B who are floating in space. A sees B passing by and vice versa. A sends signals to B every minute. According to A since B is moving his clock will be ...
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1answer
371 views
Conservation of angular momentum across different reference frames?
I saw the following problem from the USAPhO:
A uniform pool ball of radius $r$ begins at rest on a pool table. The ball is given a horizontal impulse $J$ of fixed magnitude at a distance $\beta r$ ...
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2answers
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Why does the (relativistic) mass change & why?
I studied that when an object moves with a velocity comparable to the velocity of light the (relativistic) mass changes...but I am really eager to know how does this alteration take place....If anyone ...
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4answers
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Questions from elevator ride
I like to play inside the lift (elevator). For instance, there are bars attached at the side of the lift, and I like to hold my body up using my two hands on the bar. I realised that I actually feel ...
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Does the speed of light vary in noninertial frames?
The speed of light is the same in all inertial frames.
Does it change from a non-inertial frame to another? Can it be zero?
If it is not constant in non-inertial frames, is it still bounded from ...
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1answer
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Condition for circular orbit
I am a little confused about the condition for circular orbit. Goldstein's Classical Mechanics has the condition for circular orbit as $$f^'=0\tag1$$ where $f^'$ is the effective force. I understand ...
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3answers
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First Postulate of Special Relativity: What does it mean?
Wikipedia has this quote:
Special principle of relativity: If a system of coordinates K is
chosen so that, in relation to it, physical laws hold good in their
simplest form, the same laws hold ...
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1answer
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Time dilation - why the observers see each other the slow one but then one of them is older or younger?
I'm in trouble with time dilation:
Suppose that there's two people on the Earth (A,B), they are twins and each other has a clock. (So they are at the same reference frame). B travels in a spaceship ...
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1answer
194 views
What is the speed for an object that travel close to the speed of light?
I have some questions regarding Einsteins theory of Relativity that should be fairly easy to answer. Lets say we make an experiment where we have a rocket (with an astronaut inside) that travels very ...
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7answers
390 views
Relation between coordinates and frames of reference
I always get a little uneasy that all the theories I can think of (at least since Newton) are constructed in a way such that they would be true in heaven and on earth ... but we can never go ...
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2answers
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motion in the body-fixed frame?
This is really basic, I'm sure: For rigid body motion, Euler's equations refer to $L_i$ and $\omega_i$ as measured in the fixed-body frame. But that frame is just that: fixed in the body. So how ...
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3answers
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Does the Lorentz transformation not apply to light?
Since you would know that light always travels at the constant velocity with respect to all frame of reference ....according to relativity whenever we are traveling at speed of light our time with ...
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1answer
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Molecules motion in the moving frame, made it as a non inertial frame [closed]
Since according to relativity moving frame is equivalent to rest frame ... physical laws hold on in the both frame in the same way. Now imagine a isolated jet which moves at sonic velocity .. jet is ...
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1answer
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What is the difference between observer, frame of reference, and gauge?
It seems to me that there is considerable relationship between the three concepts: frame of reference, observer, and gauge. How do they overlap?
My current understanding is that an observer with a ...
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1answer
167 views
Time dilation at the speed of light
Does a massless particle travelling at the speed on light in a vacuum (c) experience an infinite time dilation effect?
i.e. Would the time dilation extend from the perspective of the massless ...
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Would time freeze if you can travel at the speed of light?
I read with interest about Einstein's Theory of Relativity and his proposition about the speed of light being the speed limit for anything with mass. So, if I were ...
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1answer
306 views
Curvature of spacetime in only required to explain tidal forces?
I'm a bit confused about the equivalence principle in GR.
I'm quoting from Wikipedia:
An observer in an accelerated reference frame must introduce what
physicists call fictitious forces to ...
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2answers
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Would the arms of a rotating ice skater still move outwards if there was no other object in the universe?
If there is no other object in the universe apart from a rotating ice skater, then nothing can be used as a reference frame. Would it make any sense to say that the skater is rotating? If so, rotating ...
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1answer
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Would we feel the rotation of a rotating habitat?
Assume that a space habitat is shaped like a can with the "top" open.
lets say we attach the can's top to a string with an astronaut standing on the base. We then rotate the can in deep space using ...
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2answers
131 views
Effect of gravity at near-lightspeeds
Let's say I'm in a space station, hurtling towards our galaxy nearly close to the speed of light. From my reference frame, I see the galaxy coming towards my ship at the same speed.
I pass the Sun, ...
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1answer
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Why can we use just one angular velocity vector to describe the rotation of a whole non-inertial reference frame?
The other day in class the professor was explaining non-inertial reference frames. We were working out how to find the acceleration of a point as measured from the non-inertial reference frame, and ...
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1answer
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Accelerating elevator?
If your in an elevator accelerating downwards faster than gravity, would you be pushed up to the ceiling? Since gravity cannot match the acceleration of the elevator, you're wouldn't be able to move ...
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How fictitious are fictitious forces?
How fictitious are fictitious forces?
More specifically, in a rotating reference frame i.e. on the surface of the earth does an object that is 'stationary' and in contract with the ground feel ...
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1answer
125 views
What would happen to electronic circuits when traveling near the speed of light?
Imagine a space ship, loaded with all sorts of computer systems, traveling near the speed of light.
Electricity itself is very fast, and can reach speeds close the speed of light. (up to 99% ...
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2answers
606 views
How can time be relative?
I don't understand how time can be relative to different observers, and I think my confusion is around how I understand what time is.
I have always been told (and thought) that time is basically a ...
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1answer
132 views
In What Frame of Reference does the Special Theory of Relativity Operate? [duplicate]
Possible Duplicate:
Time Dilation - How does it know which Frame of Reference to age slower?
This has bugged me for years.
According to the theory of relativity, the faster an object ...
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1answer
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Einstein's Gedanken Experiment that lead to the Special Theory of Relativity
Once, I read that Einstein founded the special relativity theory by imagining how an observer moves at the speed of light.
How does this thought experiment work? How to reach from this imagination to ...
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Does the “Andromeda Paradox” (Rietdijk–Putnam-Penrose) imply a completely deterministic universe?
Wikipedia article: http://en.wikipedia.org/wiki/Rietdijk–Putnam_argument
Abstract of 1966 Rietdijk paper:
A proof is given that there does not exist an event, that is not already in the past for ...
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1answer
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How to explain relativistic mass with 2 moving systems, but not 3?
All the visual explanations I know work in some kind of "If you are moving relative to something A, while inside A something is moving, the stuff in A has to move slower due time dilation and ...
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Do particles have different spins in different frames of reference?
Let's say we have two photons, whose momentum vectors point to opposite directions. Also spin angular momentum vectors of the photons point to opposite directions. (Sum of spins is zero)
Now we ...
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1answer
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Thought experiment about acceleration
Case 1: two people wake up in spaceships accelerating at 1g. They can measure or observe anything inside the room but not outside. They couldn't determine if they were on a spaceship or on earth. ...
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How does time dilation work without a privileged reference frame?
As I understand special relativity, light travels at the same speed in all reference frames.
What I fail to understand is why time dilation would occur in one reference frame, but not by an equal ...
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Time Dilation - How does it know which Frame of Reference to age slower?
Okay, I'm asking a question similar to this one here: Time Dilation - what happens when you bring the observers back together?. Specifically, I am curious about a specific angle on the second part of ...
