Term
Einstein concluded that if an _________ was traveling near the speed of light, he would measure the light moving away from him at c, 300,000 km/s. 

Definition


Term
All the laws of physics are the same in all ______________ moving frames of reference. 

Definition
uniformly First Postulate of Special Relativity 


Term
A spaceship needs an object to ____________ its speed. 

Definition


Term
A space ship can/cannot measure its speed relative to empty space. 

Definition


Term
All ___________ of ____________ are arbitrary. 

Definition


Term
Einstein reasoned that the constancy of the _____________ unifies time and space. 

Definition


Term

Definition
Amount of space traveled compared to the time of travel. Speed = space/time 


Term
_______________ can vary the speed of light in empty space? 

Definition


Term
If the speed of a baseball were constant and if it were thrown at you at 5 m/s. At what speed do you catch the baseball? 

Definition


Term
If the speed of a baseball were constant and if it were thrown at you at 5 m/s from a truck traveling away from you at 60 m/s. At what speed do you catch the baseball? 

Definition


Term
If the speed of a baseball were constant and it were thrown at you at 5 m/s from a truck traveling toward you at 60 m/s, what speed do you catch the baseball? 

Definition


Term
The speed of common objects is _____________. 

Definition


Term
From the frame of reference of the photon. How long does it take you to travel from one end of the universe to the other? 

Definition
The journey takes no time. Since you are going the speed of light, you are not traveling through time, you are only traveling through space. 


Term
Does light travel through space or time? 

Definition
Light only travels through space. It never travels through time. 


Term
If you could travel at the speed of light, would you travel through space or time? 

Definition
All of your travel would be through spaceyou would not travel through time. 


Term
When you walk, do you travel through space or time? 

Definition
When you walk you travel both through space and time, but mostly through time. 


Term
When you stand still are you traveling through space or time? 

Definition
When you stand still, all your travel is through time. 


Term
Is time an absolute quantity? 

Definition
No. Time dilation. The spaceship example shows that time is not absolute 


Term

Definition
Any device that measures periodic intervals 


Term
If a flashing clock is in a space ship moving close to C. What does the clock look like to the people on the ship? 

Definition
It is the correct time, moving at the correct intervals 


Term
If a flashing clock is in a spaceship moving close to C. What does the clock look like to someone outside the ship? 

Definition


Term
Alpha Centauri is 4 light years away. How long, traveling close to C, does it take you to go there and back? 

Definition
Not long. If you go at close to C, with time dilation, you are traveling through space, not time. 


Term
Alpha Centauri is 4 light years away. How long will it take a person to get there and back according to a person on Earth? 

Definition
8 years. If the traveler goes close to C, in Earthâ€™s frame reference it will take 4 years to get there and 4 years to get back. 


Term
A person moving close to C can keep jumping into the future when they come back to Earth. Can they go back to the past? 

Definition
No. Time only travels one wayforward. 

