In: Physics
consider a cube of sides l0 traveling parallel to one side. At what speed would the density of the cube double?
Initial state (rest) :
                    
density = 
, mass = 
, length =

                   
density, 
 = mass/volume =
   
Final state :
                   
density = 
,
                   
mass = 
 ,       length = 
                  
density, 
 is =
                                          
For
                           
                     
                       
therefore the density will be doubled if it travels with a speed of 0.707c