1. D

    Special Relativity - Twisted contradiction?

    Can anyone explain how relativity works in the following scenario? There are two inertial reference frames, the rest frame F0 and the moving frame F1. They have a velocity V along the x-axis. In the rest frame F0 there is a long cylinder of length L along the x-axis. Let's call the top of...
  2. L

    Special relativity question

    This confuses me. According to the examples often used in introductory special relativity theory books, if a spaceship leaves the earth and travels towards a far distant galaxy at near the speed of light. Then turns around and returns to Earth, perhaps 10 years will have passed for the traveler...
  3. G

    Special case with two falling bodies. What happens?

    I came up with this problem myself and can not reach a conclusion myself so I would like to know what you think? Two hollow bodies (e.g. two cubes) begin to fall and accelerate. I look at the problem on any moment (t=T) where the windspeed U = 5 m/s. The larger cube: side 1 m and M = 3,5 kg...
  4. J

    Problem with different reference frames - special relativity

    I have the following conditions: A plane with length L in its own rest frame moves with constant velocity with respect to the inertial system S. The inertial system of the plane is called S'. Two flight attendants A and B start simultaneously from the middle of the plane and move with constant...
  5. L

    Introductory Special Relativity book theory question

    According to the examples often used in introductory special relativity theory books, if a spaceship leaves the earth and travels towards a far distant galaxy at near the speed of light. Then turns around and returns to Earth, perhaps 10 years will have passed for the traveler and perhaps 1000...
  6. F

    Three surprising effects following The Postulates of Special Relativity

    What Three Surprising Effects Follow Immedietly The Postulates of Special Relativity I'm just wondering if anyone can help out here. I know the two postulates as set out by Einstein but just unsure of the 3 surprising effects.
  7. B

    Special type of three reservoir problem in Hydropower Project

    Dear experts, I have got trapped into one special type of three reservoir problem in one hydropower project. I like to share the problem here and hope to get correct solution of it. Please perform brain storming . Best of Luck ! Problem: Reservoir A has elevation 1246 masl, the pipe...
  8. P

    Finding the time it takes a light source to hit an observer

    The question I am trying to solve is: In A frame, a light source at rest located at x = 0 emits a pulse P_1 at t_1 = 0, emits another pulse P_2 at t_2 = t. A’ frame moves with constant speed V along X axis with A frame. Observer in A’ at X’ = 0 receives P_1 at t_1’ = 0, X_1’ = 0 (i.e. P_1 was...
  9. V

    regarding the length contraction and time dilation in special theory of relativity

    Respected Sir, as i read in relativity, some writer use inverse Lorentz's transformations equations and some other use Lorentz's transformations for solving length contraction and time dilation expressions with any logic that which one used in which situation. clear me this. with regards vikas
  10. K

    special relativity and a reflection paradox

    The law of reflection as stated on farside is: Now, before getting to my question, suppose I use a non relativistic example first. If I have a spherical mirror and have a light source "dead centre" of the mirror then any light rays hit the mirror at perpendicular angle to the surface of the...
  11. A

    Acceleration in Special Relativity

    Hi :) I'm working on how to resolve the twin paradox in special relativity for my 4th-year dissertation. I've found several different equations which supposedly allow for the calculation of the time experienced by each twin at set distance intervals from Earth, but they don't seem to work during...
  12. F

    Special Relativity effects; real or imaginary?

    Clock A is at rest in space. Clock B is traveling at a uniform velocity 0.5C relative to A and is heading directly towards A. As B passes A the clocks are synchronised. A notes the distance B has travelled after one year is 0.5 light years. Question: From B's perspective... 1. how...
  13. L

    No gravity in special relativity

    Hello, I've been looking for some solid treatment of why special relativity doesn't work with gravity. However, I was unable to find any literature regarding this topic. I know that STR deals with inertial frames and in GTR it is possible (under certain circumstances) to work in a local...
  14. F

    Is EMF generated in this special loop of wire

    A square loop of wire is kept hanging upright and has 3 sides made of copper and the lower horizontal side made of iron. The loop has its surface normal to a uniform magnetic field B. The question is: If the loop is allowed to fall while fully immersed in this field B, will an EMF be generated...
  15. D

    Artificial gravity - a special case?

    Not really sure where this might fit best, but I'll chance it here. I was wondering if perhaps someone here might help me figure this out. I'm familiar with the concept of creating an artificial gravity in a possible future space station by spinning, for example, a cylindrical structure. But I...
  16. T

    Is kinematics a special case of f=mA?

    Hi, Physics presents kinematics as derivative relations of position, velocity, acceleration (subject to initial conditions) of some hypothetically physical (real) object through real space. Kinematics is about unmotivated movement. Forces are not mentioned in the "real" HS kinematics problems...
  17. O

    Special Relativity: From an Introduction to Modern Astrophysics by Carroll and Ostlie

    1. The problem statement, all variables and given/known data Because there is no such thing as absolute simultaneity, two observers in relative motion may disagree on which of two events A and B occurred first. Suppose, however, that an observer in reference frame S measures that event A...
  18. P

    Special Lorentz Transformation Question

    I am quite confused about how to go about this question. I know the answer is a=(2/3)^0.5 S and S' are in standard configuration with v = ac, (0 < a < 1). If a rod at rest in S' makes an angle of 45 degrees with 0x in S and 30 degrees with 0'x in S', then find a. Thanks!
  19. M

    I seriously cannot do any Special Relativity Q's, humph =(

    Hi everyone. So my problem lies in that I understand the material covered, but when I attempt any questions it results in an epic fail. Could someone please lend me a hand? For example, could I post a question and have someone walk me through it please? Here goes: Q. Two spaceships A and B...
  20. M

    General & Special Relativity

    What is difference between general and special relativity?