Two professors compete to see who can lift a book with a lesser amount of force. The professor who uses a lever is more efficient than the inclined plane, once we factor in a basic double-edged sword called friction.
The Inclined Plane
The Lever
Mechanical Advantage and Friction
The Screw and the Wheel
The Pulley
Molecules in Solids
Molecules in Liquids
Evaporation and Condensation
Expansion and Contraction
Measuring Temperature
Temperature vs. Heat
Atoms
Electrons
Conduction
Volume and Density
Buoyancy
Convection
Heat as Energy
Radiation Waves
The Radiation Spectrum