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General and Special Relativity
Relativity is the theory stating that all measurements depend on the relative motions of the observer and the observed. The theories of general and specific relativity were both proposed by Albert Einstein.
813 Questions
It took awhile to figure out what you were asking with this. I assume the u in us should actually be a Greek mu, so the figure you are looking for is the micro-second, which is equal to 1 x 10-6 seconds, or one millionth of a second.
What is the speed of light while traveling through air at 30 degrees celsius?
When you look at a pencil in a cup of water and see a distorted image of the pencil it is called "Refraction". I have seen many people post statements saying light is not affected by temperature. This is incorrect. A mirage on the highway is a perfect example. Mirages are caused by hot air near the ground refracting, or bending, light rays upwart into the eyes of a distant observer.
Speed of light in a vacuum = 3.00 x 10^8 m/s
Refraction of Air at 30oC = 1.00026
Formula: n = c/v
v = 3.00 x 10^8 / 1.00026
v = 2.99 x 10^8
Well by using the equation Speed = Distance / Time.
So, if the speed is 1.35 m/s and the time is 0.4s, then 1.35 = distance / 0.4
by rearranging the equation we get, 1.35 x 0.4 = distance.
therefore the distance travelled is 0.54 metres = 54 cm.
What is a common model for Einstein's theory of gravity?
Whatever goes up and remains within the influence of earths gravity must come down, or circle the earth as a satellite.
Does gravitational time dilation apply to digital clocks?
Gravitational forces bend the fabric of space and time. Clocks relate the local measurement, so all clocks, digital or otherwise, are affected.
Why can a astronaut carry more massive equipment around on the moon than on earth?
Because anything on the surface of the moon has only
about 1/6 the weight that it has on the Earth's surface.
Do people living near the equator age slower than people near the poles?
Yes and no. Assuming that all other factors (like culture, available food, health facilities) are removed, a person on the equator will die slightly later than a person living near the poles. However, they do not age slower. Instead, they age at the same rate while time moves slower for them. This difference, however, is so totally minute that it would be extremely close to impossible to measure in real life. Factors like the cultures and food and health of these people pose factors that are factors of magnitude of greater significance than time dilation at earth speeds.
If this were a yes/no question, the answer would be yes.
How do you find velocity when only the frequency is given?
The question is incomplete. Frequency of what? If it refers to electromagnetic waves, you won't need even frequency to determine velocity (in a vacuum), because it will always be c (the speed of light). You can compute the speed of other kinds of waves if you know the frequency and wavelength, but not from frequency alone. The formula is frequency x wavelength = velocity If the waves are electromagnetic, and you have only frequency, you can compute the wavelength using the same formula.
Importance of hygiene among school children?
good hygiene n sanitation at every level n stage specially at school level is very imp...to keep our self healthy n fit.
How much force it takes to move an elephant?
It depends on how you want to move it. To lift it, the force will need to be greater than the weight of the elephant. To push it, you will need sufficient force to both displace its mass and overcome the friction between the elephant's feet or body and the surface it rests on. I think before I did anything else, I'd entice it with an apple. Dead elephants I leave to Phyicists who have nothing better to do.
Has Einsteins theory of relativity been completed?
Depends what you mean by "completed."
Both special and general relativity are "complete" in that they fully describe that part of the Universe that they INTEND to describe. However, neither describes EVERYTHING. General relativity, for example, is a more complete theory than is special relativity. However, even GR is useful only for gravity, saying nothing about electro-magnetism (EM) in our Universe.
Einstein was fully cognizant of this fact, and figured it would take a decade or so AT MOST to add EM to a fuller theory of relativity. Unfortunately, he was wrong -- not only is EM no closer to being combined with GR today than it was in 1915, but we now know that there are other forces we need to integrate into a more general theory! And even WORSE, we now know about quantum mechanics, which is mathematically IMPOSSIBLE to combine with GR.
The final "completion" of relativity -- an combination of all forces with GR and QM -- still awaits us. If any person is able to devise a "Theory of Everything," s/he would go down in history in the same vein as Einstein or Newton.
Did Einstein conceive theory of relativity while riding a bicycle?
The general consensus is yes, Albert Einstein conceived of his theory of relativity while riding his bicycle. It is said that:
"while riding his bicycle at night Einstein observed that [the] beam cast from his headlamp always traveled at the same speed whether he was cruising at a quick speed or coasting to stop."
Thus the theory - light from a moving source has the same velocity as light from a stationary source.
Unfortunately, this information is merely a "tale." It has not been historically proven.
Can the energy of a photon be zero?
No. But if the photon has a very large wavelength (and a very small frequency) its energy can be very close to zero.
Special relativity can be used to study an object in which frame of reference?
Special relativity can be used to study an object in physical events.
The bending of light because of it's change in velocity?
That's "refraction".
Note:
The bending of light is due to its change in speed.
Bending alone would constitute a change in velocityeven if speed didn't change.
If something is infinitely small can it be crushed?
Atoms can be crushed, as can quarks and electrons. However, you are speaking in a theoretical way because nobody has proof that infinitely small particles exist. It is actually depending on the substanse of the particle and which of the many dimensions it responds to. At the level of quantum physics, particles alter between energy and matter, so, if you are talking about quantum physics, no they cannot be crushed. Now, remember that there is enough matter in your fingernail so that if it was all packed closely together it would be smaller than an atom. So, you can simply unpack all the matter and then crush it. I have no idea why you would want to, tough. It is a waste of energy. There is a simpler answer. It's important to get some definitions first. Crushing implies making smaller. Infinitely small is an abstract, not concrete concept meaning small to an infinite degree, which means a size that cannot be made smaller. Therefore, the answer is no.
You will be contacted shortly what are they implying are they going to contact me today or tomorrow?
"Shortly" is quite meaningless. All they have told you is that they will contact you.
If they had a specific time in mind, they would have said so. "Shortly" means that
they don't know either.
Give it a comfortable, reasonable period of time. When you feel that plenty of time has
gone by and you haven't yet been contacted, then it's your job to contact them again.
