Google Map will not display in ASP.NET Master Page

Hello friends, I am creating Property website. I want to use the google map in my site. Everything works fine when I put the code in a page without master page but nothing displays when using the Master Page then it doesn't work with ContentPlaceHolder.
<div id="dvMap" runat="server" style="width: 600px; height: 600px"> </div> <asp:HiddenField ID="hfLat" runat="server" /> <asp:HiddenField ID="hfLon" runat="server" /> <asp:Button ID="btnSave" runat="server" Text="Save" onclick="btnSave_Click" CssClass="join" /> <script type="text/javascript" src="http://maps.googleapis.com/maps/api/js?sensor=false"></script> <script typ ...