Frame Definition and 1000 Threads

Could anyone quickly explain how the zero momentum frame works in 2 dimensional collision problems? I really don't understand at all. Thanks

Structural integrity is a significant matter for aerospace engineers. The Air Force is apparently investigating the possibility that Boeing is liable for the structural "defect" in F-15's. Life extension is a critical matter in aerospace and nuclear industries as highly engineered systems...

[SOLVED] Simple pendulum: does the period change in a horizontally accelerating frame Homework Statement Simple pendulum which is 5.0m long. What is its period when it is in a truck accelerating horizontally at 5.0m/s/s? Homework Equations w = sqrt(g/d) w = 2pi/T The Attempt at a...

According to Einstein's relativity theories, each observer is afforded a frame of reference which can be considered central and stationary. What would the universe look like to the frame of reference associated with a photon observer. Would all things be moving past the photon at the velocity...

hello! I am an engineering student and am participating in a RC Car raacing comp in my college. The comp requires us to contsruct a RC car using either DC motors or miniature IC engines (4cc-6cc). The track will have many obstacles like sand pits, oil spills etc. The objective is to complete...

Homework Statement Consider a body falling from a tower in the northern hemisphere at approx 40 degrees latitude. The body is seen to have a displacement to the east. Explain the origin of this displacement qualitatively from the point of view of a non-inertial observer. What local effect is...

does the temperature of a body depend upon the frame of reference from which it is observed?

I'm sorry, this topic has certainly already been covered, but I didn't find what I need. I'm trying to compute x(t) in an inertial frame if a rocket has a constant acceleration "a" as measured with accelerometers inside of it. I made these (clearly wrong) computations: In a co-moving...

Hi there, I am doing some measurement using an accelerometer. I am rather confused with regards to whether I should be see an accelerometer as a non-inertial or an inertial sensor. I have with me 2 commercial accelerometers evaluation board (analog to computer interface). One by the...

I was reading a physics textbook. It is stated that force is defined by mass and acceleration (a force of 1N causes a mass of 1kg to accelerate at 1ms^-2). In later part, it is stated that mass is defined by force and acceleration (a mass acted by a force of 1N accelerates at 1ms^-2 is 1kg). As...

Doubt on FRAME of REF(Its killing me!Help) Hello Guys I am really fascinated by Theory of Relativity and although its not in my educational syllabus(not a phy scholar) , I really study a lot about it. Now coming to the point , I have a doubt on FoR and it may be basic, so I hope you...

A train moves in a straight at a constant speed u. A boy on the train throw a ball of mass m straight ahead, along the motion of the train, with a speed v with respect to himdelf. a)What is the KE gain of the ball measured by the boy? b)What is the KE gain of the ball measured by a man...

1. http://img337.imageshack.us/img337/520/fic06p090bk7.png http://img337.imageshack.us/img337/2763/vqc06p090je0.png [/URL] 2. \sumMaboutapoint \sumFy \sumFx 3. Well firstly i just looked at it as a whole to see if i can figure out any of the reactions at F or B. I am confused...

Kinetic energy is 1/2mv^2, and velocity varies depending on velocity of the observer, so does kinetic energy also vary depending on the velocity of the observer? for example, someone sitting in a bus who slides a 2 kg brick down the center isle of the bus at 5 m/s could say the has a kinetic...

Homework Statement I don't really understand how to approach problems like these A lift has a downward acceleration of kg (k<1). Inside the lift is mounted a pulley, of negligible friction and inertia, over which passes an inextensible string carrying two objects of masses m and 3m. a...

Homework Statement Nucleus A,which has rest mass m_A,collides with nucleus B,which has rest mass m_B.In the laboratory frame,nucleus A has energy E>m_Ac^2 abd nucleus B is stationery.Find the total energy of the system in center of mass frame in terms of m_A,m_B and E. The Attempt...

does an object with constant acceleration follow Newton's laws? with constant velocity? a stationary object? i think the last two are true, but I'm confused whether a constant acceleration (m/s/s) of whatever still applies to an inertial frame or is a noninertial frame? because in a sample...

Just simple question to check Homework Statement A muon formed in the high Earth's athmoshere travels at speed v=0.999c for a distance of a L=4.6 km before he decays.How long does he live as it measured in his frame? The Attempt at a Solution t=\frac{L/\gamma}{v}

I had a question that I was hoping someone could answer for me. If light passes next to a massive rotating object such as a black hole, would the affects of frame dragging cause a blue shift or would the light essentialy travel at a speed faster than the C?

Homework Statement A frame hung against a wall is suspended by two wires attached to its upper corners. If the two wires make the same angle with the vertical, what must this angle be if the tension in each wire is equal to 0.75 of the weight of the frame? (Neglect any friction between the...

the magnitude and direction of vector can be described without using refrence frame. (true or false) . Please explain .why and why not

Came across the following interesting problem : Two explosions take place at the same place in a rest frame with a time separation of 10 s in that frame. A) Find the time between explosions, as measured in a frame moving with a speed 0.9 c with respect to the rest frame according to...

Suppose an empty space and two points. The distance from point A to B is d = k . t^2 k=constant t = time The question is: Which point is an Inertial Frame of reference ? Suppose an empty space and two references frames. A is rotating at w with center B. But B is...

A ball is thrown with initial speed vo up an inclined plane. The plane is inclined at an angle(fi) above the horizontal, and the ball's initial vecity is at an angle (theta) above the plane. Choose the axes with x measured up the slope, y normal to the slope and z across it. Write down Newton's...

In a theoretical wave that does not need a medium, not necessarily EM. the speed of the wave is given by : v=fl where f is frequency and l is lamda, wave length suppose there is a stationary wave generator, we can easily measure f and l from any arbitrary point. if we move towards the...

I am standing (yes, the question actually goes like this!) on a level floor at the origin of an inertial frame S and kick a frictionless puck due north across the floor. a.) Write down the x and y coordinates of the puck as functions of time as seen from my inertial frame. (use x and y axes...

what is an inertial frame of reference ? Simple ?

What forces affect on the Moon in the Inertial frame of reference which is the Sun? +gravity form the Sun +gravity from the Earth +centrifugal force from the rotationary movement of the Moon round the Earth is this list correct?

we know kinetic energy of a system from a certain frame of refrence is the sum of kinetic energy in the c.m framee of refrence that moves translationally to the previous frame and the kinetic energy of c.m from that frame. but what if the i choose the frame attached to the c.m such that it...

I read the entry about the Ehrenfest rotating disk paradox on Wikipedia, but the entry does not actually answer my question about what happens to the circumference of the disk in the "resolution of the paradox" section. All I want to know is what happens to the circumference of the rotating...

Let (t,x) be coordinates of some point P in some inertial frame O. Suppose that at (0,0) there is a particle that has velocity u and acceleration a in the frame O. If the origo of a frame O' is attached to this particle, then what are coordinates (t',x') of the point P in the frame O'? Or does...

I was just wondering about the following problem. Suppose that you have an arrow placed in a tube. If the arrow travels at a relativistic speed, does there exist a frame of reference such that the arrow is completely in the tube with extra tube at its ends? Does there exist a frame of...

Homework Statement Two spheres of equal radius and masses 5.00 kg and 15.0 kg are sliding towards each other along the same straight line across a frictionless, horizontal surface. Vi1 = 15.0 m/s and Vi2= -9.00 m/s, respectively. During the collision, 25% of the total initial kinetic energy...

Dan Oritii's talk is worth listening to. slides: http://www.matmor.unam.mx/eventos/loops07/talks/PL4/Oriti.pdf audio: http://www.matmor.unam.mx/eventos/loops07/talks/PL4/Oriti.mp3 The first half is an introduction to Group Field Theory (GFT) and the second half gives some exciting unpublished...

Although is against the spirit of GR, isn't the vaccumm (at QM level) a preferred frame of reference?, or if Dark Matter exist shouldn't we measure the speed of light respect to it as it was thought to be made whenever you believed in aether ?. Then somehow Einstein was wrong and there a...

Hello, Every definition of an inertial reference frame that I have read stated that it is a frame in reference in which Newton's laws are valid. But is it possible to define it in this way: it is a coordinate system that is not accelerating relative to some absolute reference point. Is there...

If I had a perfect fluid I could write the stress energy tensor in the rest frame of the fluid as a nice diagonal tensor with [rho,p,p,p] and use this to solve the field equations. Pressure is just random internal motions, so what happens if all the particles in my perfect fluid decide to...

Homework Statement How can i define a perfectly inertial frame ?

Hi pervect I was going to put this material in the thread where we discussed this topic but I'm unable to locate that thread. Sorry for the unorthodox creation of a new thread for this. I just thought it was important to talk about. :) I've been thinking hard about our discussion about the...

(There are video clips embedded in the article.) I might have missed it, but did it even occur to the authors that some people don't like this music? Anyway, someone showed me this article, and I thought it was interesting enough to pass along. I don't have any insightful comments at the...

Hello Everyone, I'm new to this forum, I've to say here is one of the greatest physics communities in the net and I'm really glad I have the opportuninty to use the huge amount of information presented here. By the way, I have a question about Electromagnetics: Consider two stationary...

Why does an object far away looks like it's going very slow when it's going really fast? And then the object seems really fast when it's near me. I just started driving and I always try to find an answer but really can't. Thanks :)

What is the difference, if any, between frame fields and coordinate bases?

if p_{tau}>>m_{tau} and we boost along the lab momentum of tau to go to its rest frame and defining this boost direction as Z-axis and looking at its decay product nu_tau and pi^- coming back-to-back along this Z-axis. here, the question is whether the tau spin in the rest frame is the same as...

One way to attack a satellite in Earth orbit is to launch a swarm of pellets in the same orbit but in the opposite direction. Suppose a satellite in a circular orbit 500km above Earth's surface colides with a pellet having a mass of 4g. What is the KE of the pellet in the reference frame of...

A friend and I have been discussing what we think is an error in our textbook (either that or a misunderstanding on our part). The book gives an example in which two protons are initially traveling parallel to one another in the same direction with equal velocity. We think that since the...

Homework Statement An inertial frame R in which the particles’ positions and velocities are related by A1= - m2 (A2) / m1 V1 = - m2(V2) / m1 at time t = 0. Show that these relationships persist at all subsequent times. Homework Equations The Attempt at a Solution...

Suppose that we choose an inertial frame R in which the particles’ positions and velocities are related by A1= - m2 (A2) / m1 V1 = - m2(V2) / m1 at time t = 0. Show that these relationships persist at all subsequent times.

Sorry for the trivial (and certainly already covered) question. Does a body's weight change with the ref. frame? If I had a very long scale on which the body can move without friction, would I observe the scale to sign different values according if I am stationary with the scale or with the object?

Homework Statement The steel ball is suspended from the accelerating frame by the two cords A and B. The angles (they are on the inside) are both 60 degrees. Determine the acceleration of the frame which will cause the tension in A to be twice that in B. The acceleration is going to the...