We started with a problem involving gravitational potential energy, kinetic energy, and elastic potential energy with a mass and a spring.
Work and energy both have units of Joules.
Made an analogy to a trampoline for the spring. Used the concept of conservation of energy. Energy changed forms a few times.
Another problem involved friction and an incline with and without friction. The version with friction was a bit more complicated and required more algebra, factoring out common terms.
For a calculus problem, getting the volume in terms of one variable using a ratio of radius/height was helpful.