Grandpa: (groan) "Yes, what is it?"
Grandson: "In today's class we analyzed the flight of an arrow with snapshots. Now the arrow moves in flight towards its target, but those snapshots don't show any movement which is a paradox. And I know none of those snapshots will show any movement no matter how many snapshots are taken. And if you say that all you need to do is measure the time between snapshots, that will mean there are gaps between snapshots and there are no movements in those gaps. Grandpa, grandpa I'm so confused."
Grandpa: "Why don't you ask your teacher these questions? That's what he gets paid for."
Can you help Grandpa out of this jam?