In my magento site currency switcher is not working in home page only but after clearing cache only switching currency in home page ![enter image description here]
This happens due to block cache.
To fix this behaviour you need to disable caching for this particular block. It can be done by adding cache_lifetime="1" parameter to our shortcode.
Check this link for full shortcode samples http://nwdthemes.com/2014/10/16/magento-new-products-block-change-currency/