# AcevesJacinto45

### From Bytesized Wiki

MikeFebruary 18, 2011 Time slows down for the object monvig, relative (and this is the important part) to an observer. Think of it like this (and this is an oversimplification): Lets say you are sitting in your car on the side of the road and a car goes past you at 60 mph. (Think of that car as light . ) The speed of the car relative to you is 60 mph (the speed of light).Now you start your car and accelerate to 30 mph (1/2 the speed of light). Another car then goes past you at 60 mph, but now since you are monvig at 1/2 the speed of the car that just passed you, it appears to you that the car in front of you has slowed down, as it is now pulling away from you at a relative speed of only 30 mph. With me so far .Now here's where the relativity thing kicks in . If it's a hundred miles to the state line from where you were sitting in the car when the first car passed you at 60 mph, when that car crosses the state line it is actually a hundred miles away from someone else who would have been standing there outside your parked car.But, to you, going 30 mph when that car passes, the faster car doing twice your speed at 60 mph, will be only 50 miles ahead of you when it crosses the state line. So, to you it's like you slowed down the car in front of you by 1/2.Same thing would happen in space if a spaceship was traveling 1/2 the speed of light. Everything would look normal to an observer on earth, but time would slow by 1/2 to the astronauts in the spaceship.And, this is not just theory. It's reality. Give you an example. GPS satellites that are in orbit above the earth rely on extremely precise internal clocks to calculate their position so that when you get a signal from them the location you get is accurate. Because they are traveling a a tiny fraction of the speed of light relative to us on earth, their clocks have to be readjusted every day by computer so they stay in synch with us.Regarding your bonus question, the question is moot. You cannot travel faster than the speed of light, or even achieve the speed of light. (Explanation reserved for your next question, perhaps.)