Some new videos about related rates in calculus are up! check them out!
A balloon fills with a gas: find the rate of change of the radius as air is pumped in
Water fills a conical tank: find the rate of change of the depth as it fills with water
A ladder is pulled away from a wall: Find how fast the top of it slides down the wall
Two boats sail away from each other at an angle of 90 degrees: Find how fast the distance between them is changing
Find all of the calculus tutorials here