What is relative mechanics and what is the formula for relativistic mechanics?

LZ: Hello!

Relative mechanics is based on the theory of relativity, which is very different from classical mechanics in that it denies that space-time is absolute, and many effects cannot be explained by classical mechanics, such as: Mercury's perihelion precession, radar's echo delay, etc., and it also points out that there is an inseparable relationship between the energy and mass of matter (e=mc 2). The fundamental laws of classical mechanics are Newton's laws of motion or other mechanical principles related to Newton's laws and equivalent, which are mechanics before the 20th century and have two basic assumptions:

One is to assume that time and space are absolute, that the measurement of length and time intervals is independent of the motion of the observer, and that the transmission of interactions between matter is instantaneous; The second is that all observable physical quantities can be determined with infinite precision in principle. Since the 20th century, due to the development of physics, the limitations of classical mechanics have been exposed. As the first assumption is made, it is actually only applicable to low-speed motion compared to the speed of light.

In the case of high-speed motion, time and length can no longer be considered independent of the observer's motion. The second assumption applies only to macroscopic objects. In a microscopic system, it is in principle impossible for all physical quantities to be accurately determined at the same time.

Therefore, the laws of classical mechanics are generally only approximate laws when macroscopic objects move at low speeds.

This is a different system that considers low-velocity objects and high-velocity objects. To put it bluntly, speed affects time, and time is not the same in any space, it is the same as speed.

Complete. Hope it helps!

You don't even know this, huh?

The formula for special relativity: x= (x-ut) ; y=y ；z=z ；t=γ(t-ux/c^2) 。

Relativistic Mechanics:

1.Speed Transformation:

v(x)=(v(x)-u)/(1-v(x)u/c^2)v(y)=v(y)/(1-v(x)u/c^2))v(z)=v(z)/(1-v(x)u/c^2))2.Shrinkage effect: l = l or dl = dl 3

The clock slow effect should be simple: t= or dt=d 4Doppler Effect of Light:

a) = sqr ((1- )1+ ) b) The light source and the detector move in a straight line. )

5.Momentum expression: p=mv= mv, i.e. m= m.com

6.The basic equation of relativistic mechanics: f=dp dt

7.Mass-energy equation: e=mc 2

8.Energy momentum relation: e 2 = (e0) 2 + p 2c 2

The principle of relativity is the fundamental principle of mechanics.

The study of nature and the use of natural forces have been linked from the outset to the individualization of objects, the distance of one object to some other objects changing over time, and the implication of these "other" objects as the inseparable background of the objects in question.

We can't use a sequence of numbers to correspond to the position and change of the position of the object, i.e., we can't parameterize the position and velocity of the object. In his book The Mathematical Principles of Natural Philosophy, Newton clearly stated the principle of relativity in his fifth conclusion based on the three laws of motion.

Given an object, it moves relative to some objects, marks these objects, and then corresponds to these distances with a number of sequences, so that these objects become the reference objects, and the whole of the distances from the given objects to these objects becomes the reference space. The whole number corresponding to the distance is composed of an ordered system.

In this way, a coordinate system linked to the reference object was introduced. The so-called principle of relativity of premises is the equality of coordinate systems; the possibility of converting from one coordinate system to another; As well as giving the characteristics of the inside of the object and the distance of the particles inside the object and the invariance of its structure when the coordinates are transformed.

<> Galileo used the principles of physics to defend the Copernican theory of geokinesis, he applied the principle of independence of motion to explain in layman's sense that a stone fell from the top of the mast to the foot of the mast without deflecting towards the stern of the ship. Furthermore, with the famous discussion that the law of motion of objects in the cabin of a ship moving in a uniform linear motion is unchanged, the concept of an inertial reference frame was proposed for the first time.

This principle was called Galileo's principle of relativity by Einstein, and it is the precursor to the principle of special relativity. From the Galilean transformation, the principle of mechanical relativity can be derived. No classical mechanical experiment in the interior of an inertial frame can determine whether the inertial frame itself is in a state of relative rest or a state of uniform linear motion.

History of Mechanics:

The history of mechanics is a branch of mechanics and a branch of the history of science, which describes and studies the history of human beings in understanding and applying the laws of mechanical motion of objects from natural phenomena and production activities. The development of mechanics is roughly the same in terms of historical chronology and the logical order of disciplines, and this development reflects the process of gradual deepening of human understanding from simple to complex.

The establishment of Newton's laws of motion was an important milestone in the development of mechanics. Classical mechanics laid the foundation and developed according to the logical laws of the discipline itself. In modern and modern times, with the deepening of research content and the expansion of research fields, mechanics has gradually formed various branches, and in recent years, there has been a trend of cross-branch and interdisciplinary comprehensive research.

Classical mechanics cannot explain the high.

The physical manifestation of speed motion.

Elephants and microscopic physical phenomena.

The theory of relativity can explain high-speed physical phenomena more reasonably, and quantum physics can explain microscopic physical phenomena very well.

The theory of relativity is useful to theoretical physicists, but it is very cumbersome and unnecessary to explain many physical phenomena related to people's production and life with the theory of relativity. It's like you know that 20x20=400, but you still need to use 20+20+20...There is no need to explain.

Most of the knowledge of engineering physics is based on the theoretical system of classical physics.

This is the compound motion of the points. Let the absolute velocity of the moving point p be v and the acceleration be a

P-point velocity vector equation v=vr+ve (1).

Find v according to the geometric relationship of the velocity vector in the figure

Cosine theorem v= (vr 2+ve 2+2ve*vr*con( 2)) a).

where the relative velocity of the moving point p vr=r'=rω0

The point of convergence between the moving point p and the large wheel of the dynamic system (p've=op*=2r*con(2)*0

Substituting equation (a), the velocity of point p v=r 0 (1+4(con( 2)) 2+2con( 2))).

The acceleration vector equation at point p a=arn+aen+ak (2).

where the relative centripetal acceleration of the moving point p arn=vr 2 r= 0 2*r

Implicated centripetal acceleration aen=ve2 op= 0 2*2rcon(2).

The implicated motion is a fixed axis rotation of a rigid body, and there is a Goesiln acceleration ak=2 0*vr=2 0*r 0=2r 0 2

Use the cosine theorem to find the magnitude of the acceleration a at the point of vp, and the result is.

a=rω0^2√( 16(con(φ/2))^2+9)

The landlord said 2w0,I don't know how to get it.,The calculation method of this kind of problem is more dead.,It's also more complicated.。

The velocity of the small disc around o is w = w0 with respect to the large disc but the angular velocity of the large disc with respect to the ground is w = w0. So the angular velocity of the small disc relative to the ground is 2w0

The linear velocity of the small disc is v=2w0*r=2rw0(m s)**The linear velocity is v1=w0*2r=2rw0(m s), and the acceleration is 0 because the angular velocity does not change.