标题（Title） 一般不超过80个字符
The Physics Classroom
（21 个字符）
关键词（KeyWords）一般不超过100个字符
physics, physics classroom, tutorial, multimedia, animations, practice test, review questions, labs, experiments, projects, problem-solving, interactive exercises, CDs, answers, motion, kinematics, kinematic equations, Newton's laws, F=ma, vectors, projectiles, momentum, collisions, momentum conservation, energy, work, energy conservation, circular motion, planetary motion, satellite motion, gravitation, universal gravitation, circuits, electrostatics, current, electric potential, charging methods, static electricity, electricity, waves, sound, light, color, resonance, polarization, physics of music, standing waves, optics, mirrors, lenses, reflection, refraction, wave behavior, interference,
（702 个字符）
描述（Description）一般不超过200个字符
The Physics Classroom serves students, teachers and classrooms by providing classroom-ready resources that utilize an easy-to-understand language that makes learning interactive and multi-dimensional. Written by teachers for teachers and students, The Physics Classroom provides a wealth of resources that meets the varied needs of both students and teachers.
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