The Facts On File Dictionary of Physics, Fourth Edition clearly explains the language and terms that play an integral part in this important branch of science. Completely updated and revised, this edition includes approximately 320 new entries, new photographs, new pronuciation symbols, a listing of websites, and a bibliography. Current entries and back matter have been revised accordingly. Covering every aspect of physical science, this comprehensive reference is the perfect companion to the other three new dictionaries in The Facts On File Science Dictionary series.