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Can someone explain something physicsy to me
Former Member
Posts: 1,876,323 The Mix Honorary Guru
in General Chat
Ok, there is a limit on the velocity of any mass object in that it cannot exceed c, because as it does it's mass approaches infinite.
But, what if two mass based objects have both accellerated over time (maybe planets?) so they're both travelling in relation to a third object (say, the centre of the galaxy) at 75% the speed of light. If you were on either planet, you wouldn't notice, but if you observe the second planet, it is indeed travelling at 1.5x the speed of light. But that's impossible. But at the same time, the third observer in the centre of the galaxy can confirm you are both definately moving at some pace in opposite directions.
What would actually happen? Would the universe detect a relative object was travelling quite fast and so automatically slow the first object down (which maybe explains gravity, lol) or.. what?
Surely one object can't have two velocitys because then at a different time interval it would have two locations. Does not compute!
But, what if two mass based objects have both accellerated over time (maybe planets?) so they're both travelling in relation to a third object (say, the centre of the galaxy) at 75% the speed of light. If you were on either planet, you wouldn't notice, but if you observe the second planet, it is indeed travelling at 1.5x the speed of light. But that's impossible. But at the same time, the third observer in the centre of the galaxy can confirm you are both definately moving at some pace in opposite directions.
What would actually happen? Would the universe detect a relative object was travelling quite fast and so automatically slow the first object down (which maybe explains gravity, lol) or.. what?
Surely one object can't have two velocitys because then at a different time interval it would have two locations. Does not compute! 0
Comments
And anyway, neither planet is traveling at 1.5 times the speed of light. If two cars set off at 25 miles per hour in opposite directions the distance created would be as if one was stationery and the other traveling at 50mph. But neither car is actually moving that fast. The people in each car may perceive that the other car is moving faster but that doesn't mean it actually is.
Each planet would only have one velocity, 0.75 times the speed of light. The 1.5 times the speed of light would only be perceived by the people on the other planet, who wouldn't actually be able to perceive it anyway, as they'd always be ahead of any light source or signal given off by the second planet.
Man, my physics is rusty.
The speed of light itself.
The speed of light is a constant, 2.98 times ten to the power of eight meters per second. So if you're traveling a 200m/s, light will still be moving 2.98x10 to the eight m/s faster than you.
From what I remember of high school physics.
Rather interestingly, they can!
special relativity dictates that the observed velocity of an object is never greater than the speed of light.
also, events in two different locations that look like they're simultaneous to one observer, may not look simultaneous to another. Objects travelling at high velocities may experience time dilation, length dilation and all sorts of other weird stuff.
good ol' wikipedia's got some good stuff on relativity, paradoxes are always fun! http://en.wikipedia.org/wiki/Ladder_paradox
http://www.youtube.com/watch?v=SIfRZhztNos
(Only bit I could fin but there's a great episode of Cosmos on the theroy of relativity)
Basically speed is the measure of distance traveled in a unit of time. The speed of light is constant so what changes is time itself, as Randomgirl mentions. It's time that is relative.
http://www.youtube.com/watch?v=AZ6N85lNgHY&feature=related
http://www.youtube.com/watch?v=C2VMO7pcWhg&feature=related
It doesnt matter how much of a geek she says she is, the above will not help you pull her.
that's pretty much how they came about, yeah