I have gained both the "Suffrage" and "Vox Populi" badges, but I still don't understand the concept of the "10 extra votes for questions" function! The topic has been discussed on Meta, but I don't know how it works!
Voting is a network-wide thing rather than an ELU-specific thing, and I think this is answered by an Meta.SE question, What's the difference between Suffrage and Vox populi badge. It's not possible to mark this question as a duplicate of that one because it's on a different site, but please do refer to it.
Suffrage: used 30 votes per day
Vox populi: used the maximum 40 votes in a day
Broadly speaking, you can vote forty times, but ten of those votes are reserved for votes on questions. You can only use these ten reserved votes before you've used 25 answer votes.