Entities build up fall damage while being teleported. I have tested this with cows and with the player.
1. Create a new survival peaceful superflat world. You should be in y = 4.
2. Execute the command /tp ~ 7 ~.
3. Notice how you do not take fall damage.
4. Execute /tp ~ 100 ~, and before hitting the ground, execute /tp ~ 7 ~.
5. You take fall damage.
The expected behavior is that the momentum should be reset every time the entity is teleported.