All Questions
10
questions
1
vote
1
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75
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Principle of Relativity and the invariance of Newton's law in IRFs
Newton's law are form invariant under the coordinate substitutions:
$$
\tilde{x^{i}}=x^{i}+a^{i}
$$
This means that Newtons' equation of motion,
$$
F^{i}=m \frac{d^{2} x^{i}}{d t^{2}}
$$
(where $i=1,2,...
- 11
0
votes
2
answers
76
views
In galilean relativity, is an observer assumed to be at rest only to simplify calculations, or is there a physical reason for this assumption?
I am a beginner in Physics and my teacher taught us "Relative Motion" yesterday. He said that the "Observer is assumed at rest." Is the observer assumed to be at rest only to ...
0
votes
2
answers
88
views
Question about relative motion from "A Brief History of Time" [closed]
I read this example in Stephen Hawking's A Brief History of Time:
If one sets aside for a moment the rotation of the Earth and its orbit round the Sun, one could say that the Earth was at rest and ...
- 1
2
votes
5
answers
123
views
If motion relative to a frame of reference is purely relative, how do we account for the work done to move relative to the frame of reference?
I get the idea that everything is in motion, and there's no absolute reference frame for everything.
But when we consider local events, like a train passing through a town, I have trouble accepting ...
0
votes
2
answers
296
views
Why is relative motion at constant velocity the same as being at rest?
If I am a passenger who plays catching-the-ball game inside a vehicle that moves with a constant velocity in a straight road, why can I catch the ball repeatedly that as if the vehicle is at rest? How ...
user282164
2
votes
0
answers
344
views
Observer Watching a Ball Thrown Up on A Train [closed]
Let's suppose I'm on a train, moving with constant speed V1. At a time T1 I throw a ball up in the air, the ball do not accelerate but has constant velocity V2, and, in this hypotetical scenario, no ...
21
votes
5
answers
3k
views
Is it possible to stay up while riding a bike on a moving sidewalk without actually moving?
If I ride a bicycle on a moving sidewalk so that I am not in effect moving at all relative to the ground, will I fall over?
- 319
-1
votes
1
answer
1k
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While jumping in a high speed train why we fall on same place? [duplicate]
while we jump inside a high speed train why do we fall on the exact place?
as train is in high speed and we are jumping so we should fall backside. but this doesn't happen why?
0
votes
2
answers
127
views
Does it take less time to drop a ball than fire one horizontally (with $90^{\circ}$) [closed]
So I was arguing about this with my friend. If we take two balls and drop one from a certain height H and then fire another one with horizontally with some initial speed from the same height H, which ...
- 505
3
votes
4
answers
20k
views
Stone dropped from a moving train
This may look like a stupid question, but it is really getting to me. Imagine a train moving with an acceleration $a$, and a person drops a stone from the window. To an observer on the ground, the ...
- 2,758