What is Reference frame: Definition and 229 Discussions

In physics, a frame of reference (or reference frame) consists of an abstract coordinate system and the set of physical reference points that uniquely fix (locate and orient) the coordinate system and standardize measurements within that frame.
For n dimensions, n + 1 reference points are sufficient to fully define a reference frame. Using rectangular (Cartesian) coordinates, a reference frame may be defined with a reference point at the origin and a reference point at one unit distance along each of the n coordinate axes.
In Einsteinian relativity, reference frames are used to specify the relationship between a moving observer and the phenomenon or phenomena under observation. In this context, the phrase often becomes "observational frame of reference" (or "observational reference frame"), which implies that the observer is at rest in the frame, although not necessarily located at its origin. A relativistic reference frame includes (or implies) the coordinate time, which does not equate across different frames moving relatively to each other. The situation thus differs from Galilean relativity, where all possible coordinate times are essentially equivalent.

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  1. S

    What is Ann's final position in different reference frames?

    Hi, I'm quite new to relativity and I'm just going through some problems from past exam papers to prepare for an upcoming subject. The following question has me a little stumped: Betty is at the origin of her frame of reference. At a certain point in time, this also corresponds to the...
  2. H

    Defining Inertial Reference Frames in General Relativity

    How can you have an inertial reference frame in which a body can remain at rest or move with constant velocity unless you postulate the disappearance of the universe? In the Michelson Morley experiment the Earth is not moving with constant velocity, it is accelerating. So the postulates of...
  3. T

    Particle in non-inertial reference frame

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  4. K

    Falling body in a non-inertial reference frame

    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...
  5. K

    Newton's Laws and Inertial Reference Frames

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  6. A

    Determine which reference frame is inertial

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  7. O

    Titled reference frame, N2L with position and velocity

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  8. O

    How Do Moving Frames Affect the Observation of a Puck's Path?

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  9. L

    Possible webpage title: Defining Inertial Reference Frames in Classical Physics

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  10. W

    Kinetic Energy in reference frame

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  11. gabee

    Magnetism: which reference frame?

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  12. L

    Does Weight Change with Reference Frame? A Question Explored

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  13. K

    Is the intellect the absolute reference frame?

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  14. K

    Does light truly have no reference frame?

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  15. E

    What forces must be considered in non-inertial rotating reference frames?

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  16. L

    Basis for the postulate that all physics is the same for all inertial reference frame

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  17. N

    From a photon's reference frame

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  18. R

    A frame dragging experiment in an accelerated reference frame

    Hi, I was thinking about an experiment that might demonstrate frame dragging via the equivalence principle. The apparatus consists of a rotating massive cylindrical shell within a vacuum. Near the inside and the outside of the shell exist two gyroscopes with their axis both...
  19. D

    Motion in accelerated reference frame

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  20. D

    CMBR as an absolute reference frame

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  21. N

    Luboš Motl's reference frame down?

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  22. S

    Use a GEOCENTRIC reference frame to explain the earth's orbit

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  23. V

    Potential energy in a moving reference frame

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  24. Antonio Lao

    Why We Need a Reference Frame?

    Is the use of a frame of reference for the sole purpose of defining a distance? Can distances be defined without a coordinate system?
  25. T

    What is an inertial reference frame?

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  26. T

    On The Definition Of An Inertial Reference Frame

    There are various definitions of an inertial reference frame out there, but only one is really accepted by the physics community. In some places, you will see an inertial reference frame defined as a a reference frame in which Newton's law of inertia is valid. In some places, you will see...
  27. H

    How Does a Relativity Reference Frame Impact Quantum Measurements?

    In the measurement by the same quantum to compare, same quantum is the base in commonly, every measurement is more than twice progress to get a quantum. The interval in twice progress add some relativity action progress, the nature truly is part away. Relativity reference frame is reference a...
  28. S

    How Does a Pendulum Reveal Bus Acceleration in Different Reference Frames?

    Suppose we are on a windowless bus that travels parallel to the Earth's surface at a constant acceleration with respect to the Earth's surface. How can a passenger in the bus determine the acceleration of the bus? We decided we could attach a mass to a string and attach the string to the...
  29. H

    To select a good reference frame

    To select a good reference frame to avoid some phys difficulty As the reference frame based in this universe, the universe is secret enough in phys, like first explosion, huge action between mass and so on. To select the reference frame from this universe is to meet some phys difficulty. It...
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