How about adding 'cat'=> 10
to your query?
$new_query = new WP_Query( array(
'posts_per_page' => $carousel_count,
'meta_key' => 'wpb_post_views_count',
'orderby' => 'meta_value_num',
'order' => 'DESC',
'monthnum'=> $month,
'year'=> $year,
'cat'=> 10
));