It depends how quickly you hit the drive after 'ejecting" it from Windows. Most external hard drives take at least a second before spinning down which can also take a couple of seconds - so say 5 seconds to completely spin down after ejecting the drive. If you hit or move the drive hard enough during this time, this could be enough to cause physical damage that could translate into bad blocks.
In summary, don't move the hard drive until you know it's spun down.
In summary, don't move the hard drive until you know it's spun down.
You'll more than likely be fine, but as above if you're using spinny disks then wait a few seconds after ejecting/unplugging before moving it.
Or even better - ditch spinny disks for flash. - then you don't have that problem and can shake it to your hearts content.
Or even better - ditch spinny disks for flash. - then you don't have that problem and can shake it to your hearts content.