Will my application get deleted if I updated my tablet.if yes can I prevent it by moving them on my SD card?
You haven't specified your model number...
Anyway, if you update via the OTA Updates from within your phone,then the update shouldn't wipe your data/factory reset.
But just to be safe, backup your data. Copy your photos, app data, documents etc to your PC. So if the update goes wrong and it wipes your data, you can still restore your data from the backup you made.
By moving your apps to the sdcard, then still the apps will be removed after a factory reset. That would make no difference.
Hope my answer helps