Rotation

Circular motion Vector approach Moment of inertia Rotation of a molecule Problems Next topic Return to index

Rotational motion

Molecules rotate, and their rotational motion has important effects on the energies and heat capacities of gases, as well as giving a wealth of structure to molecular spectra. The rotational energies and spectra of molecules also give a method for finding very precise bond lengths and angles, and even measuring the temperature in remote and extreme environments (for example on a remote planet or in a flame).

• The first topic deals with rotation of a simple body performing circular motion.
• The second topic is a vector decomposition of the motion of a particle into radial and angular components.
• The third topic is an analysis of the moment of inertia of systems with gradually increasing complexity.
• The final section deals with the rotation of a molecule treated as a rigid body.