This question seems like it requires calculus, but it actually has a much more clever solution

Sign up with brilliant and get 20% off your annual subscription: https://brilliant.org/ZachStar/

STEMerch Store: https://stemerch.com/
Support the Channel: https://www.patreon.com/zachstar
PayPal(one time donation): https://www.paypal.me/ZachStarYT

►Follow me
Instagram: https://www.instagram.com/zachstar/
Twitter: https://twitter.com/ImZachStar

Book where I found this problem: https://amzn.to/2QTdPBP

►My Setup:
Space Pictures: https://amzn.to/2CC4Kqj
Magnetic Floating Globe: https://amzn.to/2VgPdn0
Camera: https://amzn.to/2RivYu5
Mic: https://amzn.to/35bKiri
Tripod: https://amzn.to/2RgMTNL
Equilibrium Tube: https://amzn.to/2SowDrh

►Check out the my Amazon Store: https://www.amazon.com/shop/zachstar