Uniform Motion Essay

Uniform motion can be described as the movement of an object in a straight line with constant velocity while covering equal distances in equal intervals of time along the line. According to Newton, an object remains in its state of rest or uniform motion in a straight line unless acted upon by any external force (Arnol'd, 2013). In his explanation, Newton intended to explain that a moving object will continue in motion for as long as it moves in a straight line if it is not affected by any slight force. Also, Newton's statement can be explained to mean that if all the forces cancel out in an ideal fashion, then the object remains in constant motion. We can also interpret the situation by saying that, if the object is at rest, and no forces act on it, the object will remain at rest.

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Newton's laws may also be used to describe the state of the object after it has been acted upon by the external force. These reactions can be described as momentum and the body's velocity can be analyzed according to the external forces that have distorted its uniform motion. In an illustration, the speed of a car is said t be 10 meters per second. This means that the car moves in the particular direction uniformly for every one second the car has moved for 10metres. However, newtons laws and definitions were countered by Einstein who suggested that the laws only hold in free float frames.

Free float frames can be described as frames of reference or points of reference where the motion of a body can be described according to its kinematic characteristics. On free float frames, the objects are said to move in straight lines and their speeds are constant unless affected by external forces. Within this frame of reference also, the bodies are not accelerated since their velocities do not change with time, that is constant velocity. The Newton's laws act in this frame and obey the laws since the things are weightless and the objects take their simplest form (Kuehn, 2015).

This frame of reference can also be described as the inertial frame of reference. This frame of reference describes time and space in a controversial manner. The frame describes time and space as isotropic and homogeneous and the descriptions are time independent. By homogeneous, it is intended that the frame has the same properties at every point in time and the isotropic properties define uniformity in all orientation. This further implies that the properties of one inertial frame can be used to describe the properties of any other frame on the galaxy at any one point in the initial frame.

Frames of reference are important since they help describe and predict the behavior of objects depending on the specific baseline. Einstein, however, came up with the concept of relativity. In Einstein's description, he proposed that it was difficult for a stationary body to notice uniform motion unless it was relative. He also concluded that moving observers would tend to notice things differently compared to stationary observers. In his example, Einstein stated that when one is seated on a train that is adjacent to the other when the train the latter is seated on starts moving, then it is somehow impossible to notice which train is moving unless one notices from the background objects surrounding them are also in motion.

From this illustration, Einstein went on to describe a scenario up in deep space that, if one is seated in a spaceship that is moving at constant velocity or is at rest, then a similar spaceship passes by with constant velocity, then it would be easier for one to notice the spaceship that is really moving. From this scenario, it can be deduced that there are no existing phenomena as absolute rest. For instance, if a body is at rest hypothetically, then a moving body will describe the motion of the stationary body as zero with relative to its own motion. Therefore, it can be concluded that every motion is relative, even rest.

From the above explanation, the concept of relativity is brought out strongly according to the inertial frame as the point of reference. As earlier stated, there is no such thing as constant velocity or constant motion, the speed of light is, however, an exception. The speed of lights boasts a constant velocity since it is independent of the observer's constant velocity. This can be ascertained by the fact that two observers moving in the same direction can be seen to realize the same light effect from the source irrespective of their motion.

This inference was used by Einstein to generate the equation of relativity. In order to develop the equation of relativity, Einstein described another situation in complete space. In the situation, he described that if a massive is observed by one observer to be at rest from their point of view and another observer to be moving, then one observer will tend to measure zero energy from their point of view while the other will measure limitless amounts of energy. For there to be a consistency in the laws of physics, for these two frames of reference with the observers moving in constant speed to one another, then there must be some sort of energy associated with bodies at rest and not just the bodies in motion.

Einstein made simple calculations in his paper to show these effects. However, these effects only take place when the velocities of the participants approach the speed of light. As set up by Einstein, he explained that a practical explanation for his theory cannot be achieved since the planet earth only experiences motion that is minimal hence the Newtonian laws of physics dominate. In higher velocities, the Einsteinian physics tend to differ from those of Newton since the frames of reference change. Newton suggests that a body will remain at rest unless acted upon by an external force. The other hand, Einstein suggests that there is no such thing as complete rest.

The concept of uniform motion according to Einstein only dominate in the current world since the speeds are finite. For Einstein, all motions of objects could be analyzed as relative to one another. He further goes on to say that relativity can only be actualized if the speeds of the objects approach that of light, and the relative motions characterize constant velocity. Generally, relative motion includes high speeds and fast accelerations (Brezina, 2014).

Further, Einstein noticed that a freely falling body in the gravity capsule, that is the earth, experiences increasing velocity but at a constant rate. I other words, the body is experiencing a constant acceleration. This explanation by Newton was set to be questioned and defined by Einstein. Einstein thought that if the acceleration of a body due to gravity can be explained as constant furthermore, the acceleration of the body was used to describe its position in space since it was a function of velocity and displacement. The consideration of acceleration to describe both time and space was what Einstein used to bring forward his concept equivalence.

For example, in case one places a trampoline on a flat surface that is parallel to the earth, then a ball of substantial mass is placed above the trampoline. As expected, the trampoline will sag downwards due to the effect of gravity. This curvature of the mat of the trampoline could be described as the curvature of space and time of the bowling ball due to gravity. Additionally, when a smaller ball is placed at the edge of the trampoline, it will tend to move down to where the larger ball is. This attraction can be accrued to the curvature of the mat. This phenomena Einstein explained that not only do physical objects conform to the curvature of time and space, but also light and its properties.

Due to the changes in curvature during free fall in gravity, it is difficult to distinguish between a freely falling object in gravity from a uniformly accelerating object like a vehicle or a spacecraft. This unseen controversy is what he described as the law of equivalence.

Other explanations could be provided in to describe the theory of equivalence since it is described that there is a point in the falling of an object that it may experience weightlessness. Einstein describes that, even in the presence of gravity, there are some few frames of reference where zero weight can be experienced. In the explanation of such a case, when an object like a rock is constrained in a tin or a person in a lift. Then the person in the lift drops an object while in the lift, then the observer could be able to say that the object is falling towards the floor of the lift at an acceleration that is equal to the acceleration due to gravity.

Suppose the elevator now starts moving in an upward direction and accelerates at just the same acceleration as that of gravity. If the stone is dropped at this instant, then the observer may not be able to distinguish whether the floor of the elevator is moving towards the object or the object is falling towards the floor of the elevator. From this description, there is a point in time where the object can be said to experience no force of gravity. It for this reason that the earth's orbit around the sun can be explained.

Therefore, for a free-falling body, it cannot be determined whether the body is in acceleration towards the earth or the earth is accelerating towards the body it is only but a matter of the reference frame. For a free-falling body, it can only be described according to the frame of reference to which the observer is viewing it from as either free space or in a gravitational field. However, the laws of physics still apply in all scenarios whether in free space or in the interference of gravity. An object will still accelerate or move according to the same displacement in a certain direction according to the laws of physics.

Further, it can be deduced that the curvature of time and space the sights and visions viewed from out of space could be false since the path of light could have been affected by the force of gravity. Essentially, the light from the sun changes in propagation and magnitude from the sun due to the changes in time and space. This inference, however, contradicts that of Newton hence the phenomenon of gravitational lensing.

In general, inertia forces and gravitational forces cannot be distinguished by viewing the object as it falls freely through space or in the atmosphere. The interplay of these forces can only be analyzed from different points of view which in this case is described by the frames of reference. The gravitation experienced on earth Einstein says is as a result of the acceleration of time and space through our eyes. The objects in the earth's surface only experience gravity through them as the forces travel towards the center of the earth. We are only in the gravitational force's line of action.

Also, further experiments have been carried out to verify this phenomenon. During both eclipses, of the sun, and of the moon, photographs taken from the earth signify that the stars viewed to be behind the sun could no exist from where they are viewed from due to the effect of gravity. Also, this effect was analyzed to be the redshift where Einstein predicted and said that light coming from outside heavy gravitational sources, their wavelength should be shifted to greater wavelengths. The redshift theory was substantiated in later years after Einstein's passing away and the value required to shift the light to its correct wavelength is found in Einstein's equations.

Conclusion

Einstein's theories are essential in order to understand the concept of rotation of the earth. From the above explanations, it is only in a highly homogeneous situation or isotropic frame of reference that the concept of gravitation and acceleration can be related. Further, the concept of equivalence only holds when the frame is perfectly homogeneous then from this point, two bodies falling will be accelera...