Pumping water problems are Calculus 2 work problems with changing force and changing lift distance. This Woody Calculus lesson develops the complete slice method and solves a cylindrical-tank example step by step.
Polar coordinates describe a point using distance and angle instead of x and y. This Woody Calculus lesson explains r and θ, negative radius, graphing, symmetry tests, rose curves, cardioids, limaçons, and the polar area formula.
Surface area of revolution measures the curved surface created when a graph rotates around an axis. This Woody Calculus lesson derives dS = 2πr ds, explains the x-axis and y-axis formulas, and solves the complete example y = √x on [0,4].
Arc length measures the exact distance along a curve by adding infinitely many tiny straight-line distances. This Woody Calculus lesson derives the formula, explains the ds triangle, and solves the classic hard arc length example step by step.
Washer method or shell method? This Woody Calculus lesson teaches the Calculus 2 decision rule for volumes of revolution: identify the function form, check the axis of rotation, choose the right slice, and build the correct volume integral.
Hydrostatic force problems are Calculus 2 slice-method problems in disguise. This Woody Calculus lesson explains why force equals density times gravity times area times depth, why pressure changes with depth, and how to set up the hydrostatic force integral for a circular plate.