once i connect my iphone 5 to my laptop ,i can sync everything,but the iphone is not charging while its synced???please help me out ??

Hello there, ishrath06.

The following Knowledge Base article provides some great recommendations for troubleshooting your issue:

iPhone and iPod touch: Charging the battery

http://support.apple.com/kb/HT1476

In particular:

Battery does not charge

1. Verify that the outlet being used is working.
2. Try another USB power adapter if available.
3. If no other USB power adapter is available, try connecting to a high-power USB 2.0 port (not a keyboard). The computer must be turned on and not in sleep or standby mode.
4. Try another USB cable if available.

If the issue persists, follow these troubleshooting steps.

Thanks for reaching out to Apple Support Communities.

Cheers,

Pedro.