how to destroy tanks

[marybiggles]

hi i only started playing the other day but im totally fed up of the fact that i can hit an enemy tank twice either with artilery or my tank, and then he moves his tank gun at me and wipes me out with one blast

my teamate said `aim for the hull` which i assume is the top of the tank, but that still didnt wipe out the tank!

please can somebody help where exactly am i aiming at to get a good chance of one hit disabling an enemy tank

thanks