Questions tagged [speed]
Questions regarding an object's movement, or its distance traveled relative to the time taken.
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When stars explode why can we still see them?
This might be a silly question but if light travels at the speed of light and time is frozen in that speed then why the stars we see could be dead already and not just instantly disappearing from the ...
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Is there an objective difference between space expansion and reduction in speed of light
I just read an article about the cosmological model of an inflationary universe. As you probably know it basically states that space itself is subject to an expansion over time.
Since there is no ...
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What is the Maximum Speed that can be acheived Because of Acceleration Due to Gravity?
Planets and other bodies in the universe have different ranges of gravitational fields. What is the maximum speed that can be achieved because of acceleration due to gravitational field.
In other ...
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Is Darkness Faster Than Light? [closed]
I've been looking around, and can't find a solid answer. Many websites say darkness is the speed of light due to the fact it is the absence of light, but other sources say otherwise, that in some ...
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At what rate are stars accelerating?
How fast stars accelerating away from a central point? Are they increasing in acceleration or decreasing? If possible could you please provide a plot of the acceleration of stars away from the central ...
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What would happen if a rocket traveling at speed of light would collide with a planet (like earth)? [closed]
Let's assume it is possible for a spacecraft to travel at the speed of light (I've read the interstellar book by Kip Thorne, apparently this is theoretically possible if you swing around two black ...
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Travelling at light speed(inside water) [closed]
It is a said fact that 299792458 m/s is the speed limit,nothing can go faster than this speed, or it will take an infinite amount of energy for propulsion.What we perforce in vacuum is one thing.Can ...
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What is faster than a supernova explosion?
Is a supernova explosion really fast or is it just fast, metaphorically speaking? Can you cite the fastest known phenomenon in astronomy (neutron stars, pulsars) besides supernovae in terms of ...
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Is the ratio between earth's distance from the sun and the speed of light just a coincidence?
I was doing some calculations to see how hard it would be to observe the speed of light and discovered an interesting correlation between the speed of light and the average distance from the earth to ...
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Does the Sun's light travel fast enough to have a straight path to Earth?
When we travel through space, we use a curved path following an orbit to reach our destinations.
As far as I'm aware, we could take a more straight line approach but it would require much more deltaV ...
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What is the acceleration of the stars' speed in the Universe? Positive or negative? [closed]
I have read quite different opinions about that, so can someone tell me what is the sign of the acceleration of the stars in the Universe if we accept that the center of the Universe is the beginning ...
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Does the cosmic microwave background recede at the speed of light?
Does the cosmic microwave background recede at the speed of light? Is it possible it recedes even faster because of the stretching of space?
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How is it known that Pillars of Creation are destroyed?
We can observe Pillars of Creation with 7000 years delay, but it is destroyed only 6000 years ago. How do we know that? How the information about explosion reached the Earth before light do?
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speed of light measurement
While searching for different methods of speed of light measurement, i came across one of the method of fizeau discussed below which i cannot fully understand.
In short,in Fizeau’s apparatus, a
beam ...
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Is there any way a meteor can hit at less than escape velocity?
Note: I have figured out one case: The meteor is splash from an impact on a close-in moon. I'm looking for any path from deep space.
My understanding is that anything from deep space will ...
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How fast is a comet moving when it crosses Earth's orbit?
Is it about the same as Earth's orbital speed?
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Does near light-speed travel doppler-shift the light from the target into gamma rays?
If a space ship travels at near the speed of light towards a star, wouldn't the light from the star doppler shift into gamma rays (or worse?) and become lethal to life and destructive to space ship ...
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Speed comparison of both voyagers
I came across this page which provides (mostly extrapolated) speeds of both voyagers. Assuming they are fairly accurate, any reason why the speed of Voyager 2 (5-6 km/sec) is less than that of Voyager ...
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If an object with mass were to somehow go the speed of light, would it destroy the whole universe? [closed]
Would an object with mass traveling the speed of light destroy the whole universe because it would have infinite energy / mass? According to wikipedia and other sources, it takes infinite energy to ...
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Is it possible to have two objects moving by sum speed of light (c) in the opposite direction? [closed]
I am puzzled by this question, because by the laws between the two object the relative gravitation force should be infinite. Anyways we can take two objects where the sum of speeds are equaling c (...
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Taking Advantage of Time Dilation
According to Einstein's theory of Special Relativity, one's speed in relation to a relatively stationary object would 'slow down' time on the moving object.
With this in mind, would it be possible to ...
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Faster Earth spinning speed to overcome gravity, possible? [closed]
As far as I know we stick to the surface of the Earth as its gravity is pulling us and Earth rotation is in a way reducing the gravity.
At what speed should Earth be spinning so that we all get ...
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How are the speed, distance and time of India's MOM and USA's Maven Mars missions calculated?
How do the scientists calculate the correct time to launch the Mars mission so that the satellite travel time is less? How they are synchronizing the speed of satellite with respect to earth and mars ?...
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Why don't we feel the speed of earth moving
When we move our vehicle, we "feel" the speed of it. However, when stationary, we still are moving,but moving by quiet a speed. We know that earth moves with X ...
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Is it possible to be 'still' in space?
So I was reading this answer about how galaxies are the fastest moving objects in the universe because space is expanding faster than the speed of light. This got me wondering, would it be possible to ...
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Why is the speed of light 299,792,458 meters/sec?
Ok, I am majoring in physics (4th year) and I never understood this fundamental (kinda) question. Maybe I haven't explored it enough.
For example, why does it take 8min20sec for the light from the ...
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A clock travelling "faster than the speed of light" [closed]
When a clock travels close to the speed of light as observed by us, it should tick slower.
Does this mean that, when using this clock to measure a second - it could travel much more than 300 000 km ...
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Time dilation on an object circling earth
How would a receiver on Earth hear a radio transmission from an object circling earth at 99% of the speed of light for 24 hours. The transmission from the object circulating would be non-stop.
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Is it possible that we see our solar system as a star?
A few days ago I just read here that our galaxies (one of which we are part of) move or expand faster than light,
And read here that light we see from stars is extremely old, maybe more than several ...
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Does gravity slow or speed light up?
The speed of light in a vacuum is presumably the fastest speed possible.
if gravity bends the course of light, does this imply that gravity the retards light so it is moving at a slower speed? If ...
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What is the fastest spinning rotation of a Neutron star?
What is the fastest spinning rotation of a Neutron star? I have heard that Neutron stars have a specially fast spinning rotation. What is the fastest?
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What's the fastest moving object in the universe?
We know that nothing can have proper velocities larger than the speed of light in vacuum. But are there any objects in space that get close to it? Any comets, or other objects thrown by gravity or ...
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Is the light we see from stars extremely old?
Our nearest star Proxima Centauri is 4.243 light years away from Earth.
Does that mean we are seeing light that is 4.243 years old everyday?
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What is the standard reference point for measuring speed?
Speed, as we know, doesn't exist without first having a reference point. We then say that the reference point isn't moving at all, and speed is then measured in relation to the reference point.
What ...
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