What is Inertial: Definition and 496 Discussions

In classical physics and special relativity, an inertial frame of reference is a frame of reference that is not undergoing acceleration. In an inertial frame of reference, a physical object with zero net force acting on it moves with a constant velocity (which might be zero)—or, equivalently, it is a frame of reference in which Newton's first law of motion holds. An inertial frame of reference can be defined in analytical terms as a frame of reference that describes time and space homogeneously, isotropically, and in a time-independent manner. Conceptually, the physics of a system in an inertial frame have no causes external to the system. An inertial frame of reference may also be called an inertial reference frame, inertial frame, Galilean reference frame, or inertial space.All inertial frames are in a state of constant, rectilinear motion with respect to one another; an accelerometer moving with any of them would detect zero acceleration. Measurements in one inertial frame can be converted to measurements in another by a simple transformation (the Galilean transformation in Newtonian physics and the Lorentz transformation in special relativity). In general relativity, in any region small enough for the curvature of spacetime and tidal forces to be negligible, one can find a set of inertial frames that approximately describe that region.In a non-inertial reference frame in classical physics and special relativity, the physics of a system vary depending on the acceleration of that frame with respect to an inertial frame, and the usual physical forces must be supplemented by fictitious forces. In contrast, systems in general relativity don't have external causes, because of the principle of geodesic motion. In classical physics, for example, a ball dropped towards the ground does not go exactly straight down because the Earth is rotating, which means the frame of reference of an observer on Earth is not inertial. The physics must account for the Coriolis effect—in this case thought of as a force—to predict the horizontal motion. Another example of such a fictitious force associated with rotating reference frames is the centrifugal effect, or centrifugal force.

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  1. I

    What is the approach for solving a non-inertial pendulum problem?

    Hi, I have this practice problem I'm trying to figure out. A pendulum 80 cm in length has a mass of 0.4g is suspended on the roof of a truck accelerating at 2.6m/s/s. Find a) the horizontal deviation of the mass; b) the tension in the cord. For a, I know the answer is 20.6cm but I...
  2. A

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  3. G

    Calculate Inertial Constant K I for Sphere + 4 Disks

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  4. P

    Inertial mass, invariant mass and the photon?

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  5. S

    Special Relativty and Inertial Reference Frames

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  6. K

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  7. L

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  8. F

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  9. M

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  11. S

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  12. I

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  13. M

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  14. L

    I can't understand inertial reference frames

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  15. A

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  16. J

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  17. Y

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  18. Amith2006

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  19. V

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  20. E

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  21. R

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  22. R

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  23. T

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  24. S

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    Need help with torque and angular inertial problems

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  26. M

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  27. M

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  29. F

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  32. C

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  33. M

    Speed of light measured the same by all inertial observers?

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  34. ?

    Frames of reference & Inertial frames

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  35. Reshma

    Inertial & non-inertial frames

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  36. H

    Why does the stick in a moving frame shrink vertically?

    dear friends, i have one problem regarding the inertial frames.it is said that freely falling elevator satisfies the above property.if there are two particles inside the elevator the distance betn. them will remain same as long as the distance is small.but when the distance betn. the paricles...
  37. S

    Is a Skydiver at Terminal Velocity an Inertial Reference Frame?

    1) Which object provides an inertial frame of reference? a. the tip of the moving second hand of a clock b. a rock thrown vertically upward c. a pendulum swinging with no air resistance d. a skydiver falling at terminal velocity At first I thought c might be correct, but now I am...
  38. D

    How Do We Determine Proper Inertial Frames of Reference?

    how do you determine if something is a proper inertial frame of reference? the Earth is but a car isnt? you can feel a car accelerate, even though you are in it, but you can't feel the Earth accelerate as it changes directions in its orbit.. is there a poitn after which you don't feel...
  39. G

    Spin-1 particles: Intrinsic Inertial Platforms.

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  40. K

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  41. W

    Permittivity in inertial reference frames

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  42. Hamish

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  43. T

    What is an inertial reference frame?

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  44. T

    On The Definition Of An Inertial Reference Frame

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  45. S

    Inertial and gravitational mass

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  46. P

    Inertial mass of a stressed body

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