Why don't changes in the bashrc file work on a new terminal window?
in my ~/.bash_profile have this code

if [ -f ~/.bashrc ]; then
    . ~/.bashrc
fi


@Mark have a greate answer here.

I found a link that clear that case at Unix FAQ for OSX.

It wrote 


  Bash Startup Files
  
  When a "login shell" starts up, it reads the file "/etc/profile" and then "~/.bash_profile" or "~/.bash_login" or "~/.profile" (whichever one exists - it only reads one of these, checking for them in the order mentioned).
  
  When a "non-login shell" starts up, it reads the file "/etc/bashrc" and then the file "~/.bashrc".
  
  Note that when bash is invoked with the name "sh", it tries to mimic the startup sequence of the Bourne shell ("sh"). In particular, a non-login shell invoked as "sh" does not read any dot files by default. See the bash man page for details.