Hello I purchased an ipad today and it charges fine with the usb cable when connected to an eletric socket but when i have plugged the usb cable directly into the laptop it does not charge. The Ipad is detected when connected to the laptop as it opens up itunes and allows me to sync etc but does not charge. The battery logo in the top corner of the screen does not move and it does not show up at charging in i tunes. I would rather charge via the usb cable connected to the laptop as it saves electricity. Can anyone help?