1.is(':visible')
2//Selects all elements that are visible.
3
4if($('#yourDiv').is(':visible')){
5	//do stuff in here
6}
7//or
8$('#yourDiv:visible').callYourFunction();

1.is(':visible')
2//Selects all elements that are visible.
3
4if($('#Div').is(':visible')){
5	// add whatever code you want to run here.
6}
7
8$('#yourDiv:visible').callYourFunction();