• 41 Videos, Slides, Films

• 21 Astronomy
• 17 Physics
• 9 Mechanics
• 9 Solar system
• 6 Chemistry
• 6 Exploration
• 6 Galaxies
• 6 Outer space
• 6 Space
• 6 Space flight
• 6 Stars
• 5 Engineering
• 4 Chemical elements
• 4 Chemicals
• 4 Sound
• 4 Sound-waves
• 4 Wave theory of light
• 4 Waves
• 2 Biological control systems
• 2 Biology
• 2 Brain
• 2 Central nervous system
• 2 Civil engineering
• 2 Human anatomy

• 41 Films Media Group
• 41 Infobase

• 41 English

• 1 United States

• 41 Internet videos
• 40 Video recordings for the hearing impaired

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