Relativity

A rocket leaves Earth and travels to a star that is 20 light years (one light year equals 9.46E15 meters) as seen by the Earth. The speed of the rocket is 0.8c relative to the Earth. The time for the trip as measured on by the astronauts in the spaceship is

• 25 years

• 20 years

• 15 years

• 12 years

A rocket leaves Earth and travels to a star that is 20 light years (one light year equals 9.46E15 meters) as seen by the Earth. The speed of the rocket is 0.8c relative to the Earth.  The distance from Earth to the star as measured by the astronauts is 

• 25 light years
• 20 light years
• 16 light years
• 12 light years

Which of the following statements is not true according to the theory of relativity? 

• As an object increases speed its mass increases. 
• As an object increases speed its length increases. 
• As an object increases speed its kinetic energy increases. 
• As an object increases speed its momentum increases. 

Compared to clocks in a stationary reference frame moving clocks run 

• faster
• slower
• at the same rate

We do not usually observe relativistic effects in our daily lives because 

• we are moving at speeds much less than c. 
• we are much larger than atoms. 
• we are much heavier than elementary particles. 
• we are much lighter than stars. 

What does the relativity of simultaneity say?

• Two events may occur at the same time in one reference frame, but not another.
• If two events occur at the same time in one reference frame, they will occur at the same time in all reference frames.

How many postulates are there in the special theory of relativity?

• 1
• 2
• 3
• 4

The speed of light is constant in all frames of reference.

• True
• False

Tags

NGSS.HS-PS4-3

The speed of light (c) =

• 3 x 10⁸ miles/hour
• 3 x 10⁸ meters/second
• 3 x 10⁸ kilometers/hour
• none of these

Tags

NGSS.HS-PS4-1

We do not usually observe relativistic effects in our daily lives because 

• we are moving at speeds much less than c. 
• we are much larger than atoms. 
• we are much heavier than elementary particles. 
• we are much lighter than stars.