Here's a copy of the original.

https://imgur.com/im-still-trying-to-wrap-mind-around-this-o5sVz

Calvin's dad is explaining how the outside of a record spins faster than the inside.

Fun fact, I used to make PlayStation 2 games, and this fact meant that data could be loaded faster from the outside of the game disc than the inside. But discs started with first data written at the inside of the disc. So we'd pad "garbage" data at the start of the disc for faster overall load times.