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Now, we set out to compare the values of second and third row to see the effect of change in the position of event while keeping the time of event same. In the relativistic transformation, we see that time value changes just because there is spatial change in stationary reference. The time values are 0.0000052393 s and 0.0000051366 s for x = 2 m and x = 100 m respectively. This is yet another dimension of relativistic kinematics. This suggests that space and time are entangled. Individual measurements of event parameters do not only change because of relative speed (It is a foregone conclusion in relativistic kinematics). The additional point here is that time value changes simply because of change in space value (x) even when the relative velocity is kept constant.

We conclude thus :

1: Spatial and temporal values in the inertial references are different on account of relative velocity.

2: The temporal (t) values are dependent on spatial values (x,y,z). The space and time specifications of an event are entangled.

The spatial dependence of temporal parameter, as a matter of fact, is also evident from the relativistic time relation :

t = γ t v x c 2

Note the presence of spatial parameter (x) on the right hand side of the equation. Clearly, spatial and temporal values of an event are entangled.

Velocity addition

Let us consider a scenario of police car chase. The police personnel fires a shot in the direction of the criminal’s car speeding ahead. What is the velocity of the bullet? It depends on the observer. The bullet moves from the gun, which is stationary in the reference of police car. The velocity of bullet will be as per the specification of the gun. This will be the same velocity as when fired from ground. Let this velocity be u'. Clearly, this velocity is inherent to the gun irrespective of its motion. If “v” be the velocity of the police car, then according to Galilean transformation, the velocity of bullet in the ground reference, "u", is obtained by addition of two velocities :

u = v + u’

When a javelin is thrown, the velocity of javelin is sum of the velocities of the javelin thrower and the javelin itself with respect to thrower. The very idea of thrower to throw javelin while running is to leverage his/her velocity towards increasing the velocity of javelin in ground reference. Also, consider motion of two cars which are moving towards each other with velocities u and w along a straight line. The velocity of approach for any of two cars is u+w. These are well established results which are outcome of non-relativistic Newtonian kinematics.

The seemingly well defined algorithm about algebraic addition of velocity runs into serious problem when we extend this concept to high speed cases. Let us do a bit of “Gedankenexperimenten”. Let two spaceships are approaching with a velocity c/2 and 3c/4. What is the velocity of approach? Clearly, it is c/2+3c/4 = 5c/4. This is a speed which exceeds the speed of light. Take another example. Let us consider that we move to a light source like a bulb in our house. Of course, we imagine that there is no atmosphere. The speed of approach here is speed of light plus our speed of approach – again exceeding the speed of light and also rendering it a variable dependent on our motion.

On the other hand, electromagnetic theory specifies the speed of light in vacuum to be exactly c. Not only that, Michelson's experiment concluded that speed of light is a constant in all directions. Lorentz experiment proved that speed of light in vacuum is independent of motion of source emitting it. We, therefore, deduce Galilean or non-relativistic addition of Velocity is not true at high speed or in the relativistic context. This is one aspect of relativistic consideration. The other aspect emerges from special theory of relativity which embodies Lorentz transformation. Let us explore Lorentz factor :

γ = 1 1 - v 2 c 2

When v->c, γ ->∞. For v=0.999999999c, γ= 22360. When v=c, γ is undefined (a ratio with zero as denominator). When v>c, γ is imaginary. Clearly, speed of light (electromagnetic wave) in vacuum is the highest speed in nature. Matter can not achieve the speed of light. There is no question of exceeding it. This aspect of speed limit for matter has been verified experimentally, wherein it is found that a particle acquires greater relativistic mass instead of gaining speed even when it is accelerated to achieve or exceed speed of light (by continuously imparting energy). We shall describe this experiment after we have discussed about relativistic mass. We should, however, treat this violation of addition of velocity as one of the key experimental evidence that gave strong credence to special theory of relativity in the initial years.

Questions & Answers

how does Neisseria cause meningitis
Nyibol Reply
what is microbiologist
Muhammad Reply
what is errata
Muhammad
is the branch of biology that deals with the study of microorganisms.
Ntefuni Reply
What is microbiology
Mercy Reply
studies of microbes
Louisiaste
when we takee the specimen which lumbar,spin,
Ziyad Reply
How bacteria create energy to survive?
Muhamad Reply
Bacteria doesn't produce energy they are dependent upon their substrate in case of lack of nutrients they are able to make spores which helps them to sustain in harsh environments
_Adnan
But not all bacteria make spores, l mean Eukaryotic cells have Mitochondria which acts as powerhouse for them, since bacteria don't have it, what is the substitution for it?
Muhamad
they make spores
Louisiaste
what is sporadic nd endemic, epidemic
Aminu Reply
the significance of food webs for disease transmission
Abreham
food webs brings about an infection as an individual depends on number of diseased foods or carriers dully.
Mark
explain assimilatory nitrate reduction
Esinniobiwa Reply
Assimilatory nitrate reduction is a process that occurs in some microorganisms, such as bacteria and archaea, in which nitrate (NO3-) is reduced to nitrite (NO2-), and then further reduced to ammonia (NH3).
Elkana
This process is called assimilatory nitrate reduction because the nitrogen that is produced is incorporated in the cells of microorganisms where it can be used in the synthesis of amino acids and other nitrogen products
Elkana
Examples of thermophilic organisms
Shu Reply
Give Examples of thermophilic organisms
Shu
advantages of normal Flora to the host
Micheal Reply
Prevent foreign microbes to the host
Abubakar
they provide healthier benefits to their hosts
ayesha
They are friends to host only when Host immune system is strong and become enemies when the host immune system is weakened . very bad relationship!
Mark
what is cell
faisal Reply
cell is the smallest unit of life
Fauziya
cell is the smallest unit of life
Akanni
ok
Innocent
cell is the structural and functional unit of life
Hasan
is the fundamental units of Life
Musa
what are emergency diseases
Micheal Reply
There are nothing like emergency disease but there are some common medical emergency which can occur simultaneously like Bleeding,heart attack,Breathing difficulties,severe pain heart stock.Hope you will get my point .Have a nice day ❣️
_Adnan
define infection ,prevention and control
Innocent
I think infection prevention and control is the avoidance of all things we do that gives out break of infections and promotion of health practices that promote life
Lubega
Heyy Lubega hussein where are u from?
_Adnan
en français
Adama
which site have a normal flora
ESTHER Reply
Many sites of the body have it Skin Nasal cavity Oral cavity Gastro intestinal tract
Safaa
skin
Asiina
skin,Oral,Nasal,GIt
Sadik
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How can Commensal Bacteria change into pathogen?
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all
Tesfaye
by fussion
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what are the advantages of normal Flora to the host
Micheal
what are the ways of control and prevention of nosocomial infection in the hospital
Micheal
what is inflammation
Shelly Reply
part of a tissue or an organ being wounded or bruised.
Wilfred
what term is used to name and classify microorganisms?
Micheal Reply
Binomial nomenclature
adeolu
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Source:  OpenStax, Electricity and magnetism. OpenStax CNX. Oct 20, 2009 Download for free at http://cnx.org/content/col10909/1.13
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