In a strip of movie film, individual frames are separated by frame lines. Normally, 24 frames are needed for one second of film.

In ordinary filming, the frames are photographed automatically, one after the other, in a movie camera. In special effects or animation filming, the frames are often shot one at a time.

The size of a film frame varies, depending on the still film format or the motion picture film format. In the smallest 8 mm amateur format for motion pictures film, it is only about 4.

The larger the frame size is in relation to the size of the projection screen , the sharper the image will appear. The size of the film frame of motion picture film also depends on the location of the holes, the size of the holes, the shape of the holes.

A system called KeyKode is often used to identify specific physical film frames in a production. Historically, video frames were represented as analog waveforms in which varying voltages represented the intensity of light in an analog raster scan across the screen.

Analog blanking intervals separated video frames in the same way that frame lines did in film. For historical reasons, most systems used an interlaced scan system in which the frame typically consisted of two video fields sampled over two slightly different periods of time.

This meant that a single video frame was usually not a good still picture of the scene, unless the scene being shot was completely still.

Standards for the digital video frame raster include Rec. The frame is composed of picture elements just like a chess board.

Each horizontal set of picture elements is known as a line. The picture elements in a line are transmitted as sine signals where a pair of dots, one dark and one light can be represented by a single sine.

The product of the number of lines and the number of maximum sine signals per line is known as the total resolution of the frame. The higher the resolution the more faithful the displayed image is to the original image.

But higher resolution introduces technical problems and extra cost. So a compromise should be reached in system designs both for satisfactory image quality and affordable price.

The key parameter to determine the lowest resolution still satisfactory to viewers is the viewing distance, i. The total resolution is inversely proportional to the square of the distance.

If d is the distance, r is the required minimum resolution and k is the proportionality constant which depends on the size of the monitor;. Since the number of lines is approximately proportional to the resolution per line, the above relation can also be written as.

That means that the required resolution is proportional to the height of the monitor and inversely proportional to the viewing distance.

In moving picture TV the number of frames scanned per second is known as the frame rate. The higher the frame rate, the better the sense of motion.

But again, increasing the frame rate introduces technical difficulties. To increase the sense of motion it is customary to scan the very same frame in two consecutive phases.

In each phase only half of the lines are scanned; only the lines with odd numbers in the first phase and only the lines with even numbers in the second phase.

Each scan is known as a field. For more detail see curvilinear coordinates. Coordinate surfaces, coordinate lines, and basis vectors are components of a coordinate system.

An important aspect of a coordinate system is its metric tensor g ik , which determines the arc length ds in the coordinate system in terms of its coordinates: As is apparent from these remarks, a coordinate system is a mathematical construct , part of an axiomatic system.

There is no necessary connection between coordinate systems and physical motion or any other aspect of reality. However, coordinate systems can include time as a coordinate, and can be used to describe motion.

Thus, Lorentz transformations and Galilean transformations may be viewed as coordinate transformations. General and specific topics of coordinate systems can be pursued following the See also links below.

Here we adopt the view expressed by Kumar and Barve: In special relativity, the distinction is sometimes made between an observer and a frame.

According to this view, a frame is an observer plus a coordinate lattice constructed to be an orthonormal right-handed set of spacelike vectors perpendicular to a timelike vector.

There are two types of observational reference frame: An inertial frame of reference is defined as one in which all laws of physics take on their simplest form.

In special relativity these frames are related by Lorentz transformations , which are parametrized by rapidity.

These frames are related by Galilean transformations. In contrast to the inertial frame, a non-inertial frame of reference is one in which fictitious forces must be invoked to explain observations.

This frame of reference orbits around the center of the Earth, which introduces the fictitious forces known as the Coriolis force , centrifugal force , and gravitational force.

All of these forces including gravity disappear in a truly inertial reference frame, which is one of free-fall. A further aspect of a frame of reference is the role of the measurement apparatus for example, clocks and rods attached to the frame see Norton quote above.

This question is not addressed in this article, and is of particular interest in quantum mechanics , where the relation between observer and measurement is still under discussion see measurement problem.

In physics experiments, the frame of reference in which the laboratory measurement devices are at rest is usually referred to as the laboratory frame or simply "lab frame.

The lab frame in some experiments is an inertial frame, but it is not required to be for example the laboratory on the surface of the Earth in many physics experiments is not inertial.

In particle physics experiments, it is often useful to transform energies and momenta of particles from the lab frame where they are measured, to the center of momentum frame "COM frame" in which calculations are sometimes simplified, since potentially all kinetic energy still present in the COM frame may be used for making new particles.

In fact, Einstein felt that clocks and rods were merely expedient measuring devices and they should be replaced by more fundamental entities based upon, for example, atoms and molecules.

Consider a situation common in everyday life. Two cars travel along a road, both moving at constant velocities. At some particular moment, they are separated by metres.

The car in front is travelling at 22 metres per second and the car behind is travelling at 30 metres per second. If we want to find out how long it will take the second car to catch up with the first, there are three obvious "frames of reference" that we could choose.

First, we could observe the two cars from the side of the road. We define our "frame of reference" S as follows. Note how much easier the problem becomes by choosing a suitable frame of reference.

The third possible frame of reference would be attached to the second car. It would have been possible to choose a rotating, accelerating frame of reference, moving in a complicated manner, but this would have served to complicate the problem unnecessarily.

It is also necessary to note that one is able to convert measurements made in one coordinate system to another. For example, suppose that your watch is running five minutes fast compared to the local standard time.

If you know that this is the case, when somebody asks you what time it is, you are able to deduct five minutes from the time displayed on your watch in order to obtain the correct time.

For a simple example involving only the orientation of two observers, consider two people standing, facing each other on either side of a north-south street.

A car drives past them heading south. For the person facing east, the car was moving towards the right. However, for the person facing west, the car was moving toward the left.

This discrepancy is because the two people used two different frames of reference from which to investigate this system. For a more complex example involving observers in relative motion, consider Alfred, who is standing on the side of a road watching a car drive past him from left to right.

In his frame of reference, Alfred defines the spot where he is standing as the origin, the road as the x -axis and the direction in front of him as the positive y -axis.

To him, the car moves along the x axis with some velocity v in the positive x -direction. Now consider Betsy, the person driving the car.

Betsy, in choosing her frame of reference, defines her location as the origin, the direction to her right as the positive x -axis, and the direction in front of her as the positive y -axis.

In this frame of reference, it is Betsy who is stationary and the world around her that is moving — for instance, as she drives past Alfred, she observes him moving with velocity v in the negative y -direction.

If she is driving north, then north is the positive y -direction; if she turns east, east becomes the positive y -direction. Finally, as an example of non-inertial observers, assume Candace is accelerating her car.

As she passes by him, Alfred measures her acceleration and finds it to be a in the negative x -direction. Frames of reference are especially important in special relativity , because when a frame of reference is moving at some significant fraction of the speed of light, then the flow of time in that frame does not necessarily apply in another frame.

The speed of light is considered to be the only true constant between moving frames of reference. It is important to note some assumptions made above about the various inertial frames of reference.

Newton, for instance, employed universal time, as explained by the following example. Suppose that you own two clocks, which both tick at exactly the same rate.

You synchronize them so that they both display exactly the same time. The two clocks are now separated and one clock is on a fast moving train, traveling at constant velocity towards the other.

According to Newton, these two clocks will still tick at the same rate and will both show the same time. Newton says that the rate of time as measured in one frame of reference should be the same as the rate of time in another.

That is, there exists a "universal" time and all other times in all other frames of reference will run at the same rate as this universal time irrespective of their position and velocity.

This concept of time and simultaneity was later generalized by Einstein in his special theory of relativity where he developed transformations between inertial frames of reference based upon the universal nature of physical laws and their economy of expression Lorentz transformations.

It is also important to note that the definition of inertial reference frame can be extended beyond three-dimensional Euclidean space.

As an example of why this is important, let us consider the geometry of an ellipsoid. In this geometry, a "free" particle is defined as one at rest or traveling at constant speed on a geodesic path.

Two free particles may begin at the same point on the surface, traveling with the same constant speed in different directions.

After a length of time, the two particles collide at the opposite side of the ellipsoid. Both "free" particles traveled with a constant speed, satisfying the definition that no forces were acting.

This means that the particles were in inertial frames of reference. Since no forces were acting, it was the geometry of the situation which caused the two particles to meet each other again.

In a similar way, it is now common to describe [32] that we exist in a four-dimensional geometry known as spacetime. In this picture, the curvature of this 4D space is responsible for the way in which two bodies with mass are drawn together even if no forces are acting.

This curvature of spacetime replaces the force known as gravity in Newtonian mechanics and special relativity. Here the relation between inertial and non-inertial observational frames of reference is considered.

The basic difference between these frames is the need in non-inertial frames for fictitious forces, as described below. An accelerated frame of reference is often delineated as being the "primed" frame, and all variables that are dependent on that frame are notated with primes, e.

The vector from the origin of an inertial reference frame to the origin of an accelerated reference frame is commonly notated as R. From the geometry of the situation, we get.

When there is accelerated motion due to a force being exerted there is manifestation of inertia. If an electric car designed to recharge its battery system when decelerating is switched to braking, the batteries are recharged, illustrating the physical strength of manifestation of inertia.

However, the manifestation of inertia does not prevent acceleration or deceleration , for manifestation of inertia occurs in response to change in velocity due to a force.

A common sort of accelerated reference frame is a frame that is both rotating and translating an example is a frame of reference attached to a CD which is playing while the player is carried.

This arrangement leads to the equation see Fictitious force for a derivation:. From Wikipedia, the free encyclopedia. Not to be confused with Inertial frame of reference.

For other uses, see Frame of reference disambiguation. Second law of motion. Circular motion Rotating reference frame Centripetal force Centrifugal force reactive Coriolis force Pendulum Tangential speed Rotational speed.

Generalized coordinates and Axes conventions. Inertial frame of reference. This section does not cite any sources.

In this geometry, a "free" particle is defined as one at rest or traveling at constant speed on a geodesic path. Two free particles may begin at the same point on the surface, traveling with the same constant speed in different directions.

After a length of time, the two particles collide at the opposite side of the ellipsoid. Both "free" particles traveled with a constant speed, satisfying the definition that no forces were acting.

This means that the particles were in inertial frames of reference. Since no forces were acting, it was the geometry of the situation which caused the two particles to meet each other again.

In a similar way, it is now common to describe [32] that we exist in a four-dimensional geometry known as spacetime. In this picture, the curvature of this 4D space is responsible for the way in which two bodies with mass are drawn together even if no forces are acting.

This curvature of spacetime replaces the force known as gravity in Newtonian mechanics and special relativity. Here the relation between inertial and non-inertial observational frames of reference is considered.

The basic difference between these frames is the need in non-inertial frames for fictitious forces, as described below.

An accelerated frame of reference is often delineated as being the "primed" frame, and all variables that are dependent on that frame are notated with primes, e.

The vector from the origin of an inertial reference frame to the origin of an accelerated reference frame is commonly notated as R.

From the geometry of the situation, we get. When there is accelerated motion due to a force being exerted there is manifestation of inertia. If an electric car designed to recharge its battery system when decelerating is switched to braking, the batteries are recharged, illustrating the physical strength of manifestation of inertia.

However, the manifestation of inertia does not prevent acceleration or deceleration , for manifestation of inertia occurs in response to change in velocity due to a force.

A common sort of accelerated reference frame is a frame that is both rotating and translating an example is a frame of reference attached to a CD which is playing while the player is carried.

This arrangement leads to the equation see Fictitious force for a derivation:. From Wikipedia, the free encyclopedia.

Not to be confused with Inertial frame of reference. For other uses, see Frame of reference disambiguation.

Second law of motion. Circular motion Rotating reference frame Centripetal force Centrifugal force reactive Coriolis force Pendulum Tangential speed Rotational speed.

Generalized coordinates and Axes conventions. Inertial frame of reference. This section does not cite any sources. Please help improve this section by adding citations to reliable sources.

Unsourced material may be challenged and removed. July Learn how and when to remove this template message. Special theory of relativity and General theory of relativity.

Fictitious force , Non-inertial frame , and Rotating frame of reference. See, for example, Kurt Edmund Oughstun Electromagnetic and Optical Pulse Propagation 1: Spectral Representations in Temporally Dispersive Media.

These distinctions also appear in thermodynamics. See Paul McEvoy Topological Groups 3rd ed. As such, the coordinate system is a mathematical construct, a language, that may be related to motion, but has no necessary connection to motion.

Handbook of Continuum Mechanics: Essays on the Formal Aspects of Electromagnetic Theory. Metaphysical essays on space and time.

General covariance and the foundations of general relativity: Analytical Mechanics for Relativity and Quantum Mechanics. Classical dynamics Reprint of edition by Prentice-Hall ed.

Classical Relativistic Many-Body Dynamics. Theoretical Physics Reprint of the 2nd ed. Introduction to Hyperbolic Geometry. This structure allows differentiation to be defined, but does not distinguish between different coordinate systems.

Thus, the only concepts defined by the manifold structure are those that are independent of the choice of a coordinate system.

Hawking; George Francis Rayner Ellis A mathematical definition is: A connected Hausdorff space M is called an n -dimensional manifold if each point of M is contained in an open set that is homeomorphic to an open set in Euclidean n -dimensional space.

Geometry of Differential Forms. American Mathematical Society Bookstore. Mathematical handbook for scientists and engineers: Simulating and Generating Motions of Human Figures.

Lectures on General Relativity. Dynamics of the Atmosphere. Vector and Tensor Analysis with Applications. How and Why in Basic Mechanics.

Geometric Algebra for Physicists. The Theory of Relativity. Problem Book in Relativity and Gravitation. Differential Geometry and Relativity Theory: Relativity in rotating frames.

This equivalence does not hold outside of general relativity, e. Principle of relativity Galilean relativity Galilean transformation Special relativity Doubly special relativity.

Time dilation Mass—energy equivalence Length contraction Relativity of simultaneity Relativistic Doppler effect Thomas precession Ladder paradox Twin paradox.

Light cone World line Minkowski diagram Biquaternions Minkowski space. Black hole Event horizon Singularity Two-body problem Gravitational waves: Brans—Dicke theory Kaluza—Klein Quantum gravity.

Retrieved from " https: Articles needing additional references from July All articles needing additional references Wikipedia articles with GND identifiers.

Views Read Edit View history. In other projects Wikimedia Commons. This page was last edited on 2 January , at By using this site, you agree to the Terms of Use and Privacy Policy.

We first introduce the notion of reference frame , itself related to the idea of observer: Let us give a more mathematical definition: As noted by Brillouin, a distinction between mathematical sets of coordinates and physical frames of reference must be made.

The ignorance of such distinction is the source of much confusion… the dependent functions such as velocity for example, are measured with respect to a physical reference frame, but one is free to choose any mathematical coordinate system in which the equations are specified.

The idea of a reference frame is really quite different from that of a coordinate system. Frames differ just when they define different spaces sets of rest points or times sets of simultaneous events.

So the ideas of a space, a time, of rest and simultaneity, go inextricably together with that of frame. However, a mere shift of origin, or a purely spatial rotation of space coordinates results in a new coordinate system.

So frames correspond at best to classes of coordinate systems. In traditional developments of special and general relativity it has been customary not to distinguish between two quite distinct ideas.

The first is the notion of a coordinate system, understood simply as the smooth, invertible assignment of four numbers to events in spacetime neighborhoods.

The second, the frame of reference, refers to an idealized system used to assign such numbers […] To avoid unnecessary restrictions, we can divorce this arrangement from metrical notions.

This comfortable circumstance ceases immediately once we begin to consider frames of reference in nonuniform motion even within special relativity.

The term is derived from the fact that, from the beginning of modern filmmaking toward the end of the 20th century, and in many places still up to the present, the single images have been recorded on a strip of photographic film that quickly increased in length, historically; each image on such a strip looks rather like a framed picture when examined individually.

The term may also be used more generally as a noun or verb to refer to the edges of the image as seen in a camera viewfinder or projected on a screen.

Thus, the camera operator can be said to keep a car in frame by panning with it as it speeds past. Persistence of vision blends the frames together, producing the illusion of a moving image.

The frame is also sometimes used as a unit of time, so that a momentary event might be said to last six frames, the actual duration of which depends on the frame rate of the system, which varies according to the video or film standard in use.

In North America and Japan, 30 frames per s: In a strip of movie film, individual frames are separated by frame lines.

Normally, 24 frames are needed for one second of film. In ordinary filming, the frames are photographed automatically, one after the other, in a movie camera.

In special effects or animation filming, the frames are often shot one at a time. The size of a film frame varies, depending on the still film format or the motion picture film format.

In the smallest 8 mm amateur format for motion pictures film, it is only about 4. The larger the frame size is in relation to the size of the projection screen , the sharper the image will appear.

The size of the film frame of motion picture film also depends on the location of the holes, the size of the holes, the shape of the holes. A system called KeyKode is often used to identify specific physical film frames in a production.

Historically, video frames were represented as analog waveforms in which varying voltages represented the intensity of light in an analog raster scan across the screen.

Analog blanking intervals separated video frames in the same way that frame lines did in film. For historical reasons, most systems used an interlaced scan system in which the frame typically consisted of two video fields sampled over two slightly different periods of time.

This meant that a single video frame was usually not a good still picture of the scene, unless the scene being shot was completely still.

Standards for the digital video frame raster include Rec. The frame is composed of picture elements just like a chess board. Each horizontal set of picture elements is known as a line.

The picture elements in a line are transmitted as sine signals where a pair of dots, one dark and one light can be represented by a single sine.

The product of the number of lines and the number of maximum sine signals per line is known as the total resolution of the frame.

The higher the resolution the more faithful the displayed image is to the original image. But higher resolution introduces technical problems and extra cost.

So a compromise should be reached in system designs both for satisfactory image quality and affordable price. The key parameter to determine the lowest resolution still satisfactory to viewers is the viewing distance, i.

The total resolution is inversely proportional to the square of the distance. If d is the distance, r is the required minimum resolution and k is the proportionality constant which depends on the size of the monitor;.

Since the number of lines is approximately proportional to the resolution per line, the above relation can also be written as.

That means that the required resolution is proportional to the height of the monitor and inversely proportional to the viewing distance.

Wieviel auch immer.