Question

In 1965 Penzias and Wilson discovered the cosmic microwave radiation left over from the Big Bang expansion of the universe. The energy density of this radiation is 7.62

Answer 1

Note that the energy density u is given by          
          
u = Eo E^2 ---> E = sqrt(u/Eo)          
          
where          
          
Eo =    8.85E-12   C^2/N*m^2  
u =    7.62E+14   J/m^3  
E = the electric field magnitude         
Thus,          
          
E =    9.28E+12   V/m   [ANSWER]