Homework Statement
A passenger holding a parcel mass m is standing in a lift which is being accelerated upwards by a constant force F. Total mass of life plus passenger is M.
First q asks: what is the accel of the lift?
Homework Equations
The Attempt at a Solution
So i know i...
Homework Statement
A proton is traveling with a speed of v = 2.993x108 m/s. Calculate the value of the inertial mass for this proton. Assume that the speed of light is c = 3.000 x 108 m/s and that the mass of the proton is 1.673 x 10-27 kg.
[SIZE="1"]Note: Do your calculations to 4...
How are inertial frames defined in Special and General Relativity? In Newtonian physics, an inertial frame is usually defined as one in which N2 holds. Clearly this cannot be the same definition as for SR. In GR an inertial frame is one in which SR holds (I think). However, there is now a...
Hello... learning to post and into the appropriate forums. Also, can you delete previous post and how?
Quick question: Since time as we know it does not or can not 'stop'... Is there such a thing as an intertial frame at 'absolute rest'?
Thank you for any and all responses.
Bye
G
Two massive lead balls are sprayed with a thin veneer of positive charge. They are isolated and at rest in inertial frame K. The positive charge is such that the electrostatic force of repulsion exactly cancels the gravitational force of attraction. Viewed from frame K’, the Lorentz force on...
Homework Statement
We could change to inertial reference frame in a collision to follow a mass. But what would the down side be if we did?
Homework Equations
Vf1=(M1-M2)/(M1+M2)*Vi1 +2M2/(M1+M2)*Vi2
Vf2=2M1/(M1+M2)*Vi1 +(M1-M2)/(M1+M2)*Vi2
The Attempt at a Solution
This question...
Homework Statement
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Given inclined plane with mass M. The angle of inclination is Alpha (from the horizontal plane).
The plane has no friction.
On the plane block with mass m.
The whole system is moving rightwards with acceleration A0.
Find the N normal...
2 textbooks I have give postulate 2 of SR as:
"The speed of light in vacuum is constant in all inertial reference frames".
But "Classical Dynamics" by Jerry B. Marion has:
"The velocity of light in free space is a universal constant independent of any relative motion of the source and...
I found this nice book on Google
http://tinyurl.com/yh2y2zb
that does a great job explaining relativity, however, even though the conclusions make perfect sense to me so far, I'm stuck on a conceptual issue when reading over the classic thought experiments that makes me feel like I'm still...
I think I'm beginning to understand general relativity. After doing some dabbling on the history of inertial frames vs accelerated frames from the time of Aristotle I've gotten to Einstein. Finally wrapped my mind around how an object in free fall is considered to be an inertial frame as...
Is it safe to say that any object in an inertial reference frame is at a state of equilibrium?
If so.. is it safe to say the opposite: that any object in a state of equilibrium is in an inertial reference frame?
Homework Statement
A rocket travels in a straight line with speed 0.6c, where c is the speed of light in a vacuum. A wrist-watch is on board the rocket. The rocket moves past a clock tower on the earth.
a. In the inertial frame where the tower is at rest, how long does it take the watch (on...
I am confuse of what is inertial frame of reference.
Can someone explain that to me?
I need a clear explanation starting from the beginning to the end, and if possible, give me some set of example.
In Sean Carroll's lecture book is written:
"... if gravitation did not couple to itself, a "gravitation atom" (two particles bounded by their mutual gravitational attraction) would have a different intertial mass (due to negative binding energy) than gravitational mass..."
Would you please...
If we explain the origin of inertial mass with the Higgs mechanism, how do we explain the origin of gravitational mass? In other words, how does the Higgs mechanism contribute to the gravitational field of a particle?
(Note: the closest thread I've found to this is...
HI guys, i was wondering what is the difference between inertial and static friction? If a car is on a frictionless ground, does it have static friction and the inertial is the same even if it is on a rough surface right?
Is there really such a thing as an inertial frame? How would we know for sure if we were in one? Looking at space, things are moving and accelerating all over the place, it would seem impossible to tell whether a frame is really inertial or not.
Imagine you are in space and everything around...
Is a falling elevator a valid inertial frame?
The title about says it. Is a body, (frame) free falling in a gravitational field a valid inertial frame as defined by SR?
Thanks
Hi,
I was wondering: I'm sitting at my desk and on my desk lies a pen. Does the pen describe a geodesic? And is the room I'm sitting in an inertial frame?
I think the pen doesn't describe a geodesic because it's not in free fall and i think my room is a good approximation of an inertial...
Ok so here's the question I am looking at.
A piston and cylinder mechanism is connected to a crank shaft. The crank is 50mm long, the connecting rod 250 mm long and the piston has a mass of 150g. If the engine speed is w rad/sec and the crankshaft torque T Nm calculate:-
i) Max inertial...
If an inertial "observer" or state has mass and no rotation, then a massless state with rotation (i.e. having maybe a generalized rotation such as "spin," e.g. a photon) seems to be dual to that state.
Would this viewpoint then take the photon as a "matching" channel or "process" for...
Dear PF could you advise me
Whether I understand properly or not:
In an arbitrary space-time (with an arbitrary curvature) in any sufficiently little region we can go to Local Inertial Frame of Reference - sit into the free falling lift. Being there our experiments are the same as we have...
No pitchforks please (and lay off the caps with the big 'D' on them too)
Following staying up until 4am (all good stories start like this), and making small talk with a friend doing a degree in physics, we both decided to harp on about theoretical theories such as string etc, and as hours...
Hi all
Why do we actually say that Newton's laws do not hold for non inertial frames. can you folks give me an example of how Newton's laws collapse in an non inertial frame(if they do at all)
Homework Statement
Show that if an hypothetical particle has v>c in a inertial system , v>c in any other
inertial system
Homework Equations
The Attempt at a Solution
[b]1. Suppose the space time co-ordinates of two events in inertial frame S are as follows:
Event 1:
x1=x0, t1=x0/c y1=z1=0
Event 2:
x2=2x0, t2= x0/2c y2=z2=0
Show that there exists an inertial frame s' in which these events occur at the same time (i.e t1'=t2') and find the value of time...
While explaining about inertial and non-inertial frame of reference, people give this example--
http://www.phys.unsw.edu.au/einsteinlight/jw/module1_Inertial.htm
if you don't wish to follow the link, here is a simple explanation--->
there are two person and a rotating disk. Person A is in...
I'm new to the study of SR and GR. I have a question that I have not been able to find any discussion about.
In the case of two frames of reference where we are comparing events from the point of view between a 'stationary frame' (inertial) to an excelerating frame like the twin paradox is...
A professor told me that in our spacetime we are able to distinguish between different inertial frames because the cosmic microwave background looks different. If this is true then what spacetime do we live in? What would it look like mathematically. Would the det(g) not be negative?
Equivalence of inertial & gravitational mass--I need a sanity check.
Einstein, in his 1916 book Relativity, illustrates the equivalence of gravitational and inertial mass using the example of a braking train.
The example begins with the train at rest (of course) and the scenery moving to the...
In the follow link we are having a discussion about inertial propulsion: http://www.gyroscopes.org/forum/questions.asp?id=994
Bellow I transcript an open question that I’d like to share with you:
The question is: How will be the energy conservation in the following experiment:
“These...
According to the principle of relativity - a postulate for Einstein's SR and GR - any frame of reference is as valid as any other for describing phenomena and the laws of physics will be the same in the chosen frame of reference as in any other frame of reference. Taking the rotating Earth as a...
I was wondering whether or not a charge must be accelerating to produce a magnetic field. If the charge is moving at a constant speed does it create a magnetic field? I f I took a van de graff generator onto an airplane moving at a constant rate, could I measure a magnetic force? Or are magnetic...
(I realized I have a confusing post title but can't figure how to edit it..It should read "Gravitational curvature vs gravitational force"
Under 'mass' Wikipedia makes a statement:
I have a question about Newton's Second Law and Inertial Frames of Refrence. It is canon that Newton's Second Law is only applicable in an inertial frame of refrence. Newton's Second Law is the net force acting on a body is equal to the time rate of change of the body's linear momentum...
It is sometimes heard that inertial frame of reference does not actually exists and is only an ideal concept. What do you guys think?
Say, for example, An object is placed far away from all objects that can exert force on it. A reference frame is taken by taking the origin and axes fix in...
Hi All,
I am a bit confused about reference frames and inertial frames.
According to the first postulate of special relativity (if I'm right), all physical laws take their simplest form in an inertial frame, and there exist multiple inertial frames interrelated by uniform translation...
Hi all. I was trying to imagine gravitation as a causal effect of time dilation and have relatively little schooling so...
With frames of reference obviously a high degree of time dilation is attained with a relative velocity close to c. however I understand a large stellar object such as a...
Homework Statement
What is an inertial frame of reference?
Homework Equations
-A particle at rest or moving at a constant velocity in an inertial frame of reference implies that the sum of the forces acting on the particle is zero
-The tendency of a body to keep moving once it is set in...
since last time i post about the defiinition, i read up about it, how i am still a bit unclear after reading few more post about this topic :
einstein: a set of frames which move without acceleration to one another and that the laws of physics hold in the simplest-is the a definition or that...
Homework Statement
I am a bit confused about what are inertial reference frames and what is not. The text states:
"We define an inertial reference frame as a reference frame in which Newton's laws are valid... Accelerating reference frames are not inertial reference frames...
Hi all
I have to write a short essay on an application of laser technology for a class. I'm keen to write it on ICF but my uni library doesn't have a great deal of material. Can anyone link me to some reputable sources on the internet?
thanks
Hi,
I have an FEA model where all my parts are bonded contacts (no contact surfaces). I am trying to fix one end of this model and apply inertial load on the other.
However the heavy parts are penetrating into the soft ones. How do I avoid this model penetration?
Thanks,
I have heard the following oppinion:
Whether a reference frame is inertial is completely determined by whether Newton's laws are applicable for particles moving at low (that is, nonrelativistic) speeds in that reference frame.
Do you agree with it?
1. Let us consider a molecule with almost "zero" binding energy. Why does every textbook declare that it should be a molecule if we accelerate it to some high velocity? Why shouldn't it dissociate at some velocity.
2. Inversly. Consider a molecule moving with some velocity. Why it couldn't...
Why the Galileo transformations are not correct for inertial systems which are traveling close to the speed of light? What made Lorentz to correct this?
Homework Statement
You are conducting an experiment inside a train car that may move horizontally along rail tracks. A load is hung from the ceiling on a string. The load is not swinging, and the string is observed to make a constant angle of with the horizontal. No other forces are acting on...
Hi guys,
I initially posted this here ...
https://www.physicsforums.com/showthread.php?p=1871724#post1871724
... but I see by the forum rules I should have posted it independently.
First of all, am I correct in understanding that a) it is impossible for an observer to observe...