Enable email notification in task list in SharePoint

How to send a email notifications in SharePoint task list to persons who have been assigned list items?

Run SharePoint Management Shell as Administrator

$site=Get-SPWeb "http://SiteURL"
$list=$site.Lists.TryGetList("List Name")
if($list -ne $null)
{
   $list.EnableAssignToEmail =$true
   $list.Update()
}