Prevent Default on Form Submit jQuery

What's wrong with this?

HTML:

<form action="http://localhost:8888/bevbros/index.php/test" method="post" accept-charset="utf-8" id="cpa-form" class="forms">        
      <input type="text" name="zip" value="Zip code" id="Zip" class="required valid">      
      <input type="submit" name="Next" value="Submit" class="forms" id="1">
  </form>

jQuery:

$("#cpa-form").submit(function(e){
    e.preventDefault();
  });

Solution 1:

Try this:

$("#cpa-form").submit(function(e){
    return false;
});

Solution 2:

Use the new "on" event syntax.

$(document).ready(function() {
  $('form').on('submit', function(e){
    // validation code here
    if(!valid) {
      e.preventDefault();
    }
  });
});

Cite: https://api.jquery.com/on/