The Physics 2 Tutor: Learning by Example DVD series covers thermodynamics, oscillations & waves in physics through step-by-step example problems. Emphasis is placed on giving students confidence in their skills by gradual repetition so that the skills learned are committed to long term memory. Lessons continue to cover traveling sound waves, including how sound waves propagate through the air and other mediums. Grades 9-12. 40 minutes on DVD.