Internet Field Trip: Optical Illusions Learn more about optical illusions. Internet Links Distortion Illusions Are your eyes playing tricks on you? Observe the "Ponzo Illusion." http://www.sandlotscience.com/Distortions/Ponzo_Illusion.htm Distortion Illusions Watch as a triangle and a square "breathe." Observe the "Breathing Objects Illusion." http://www.sandlotscience.com/Distortions/Breathing_Square.htm Ilusiones cambiantes Participa en un juego de ilusiones ópticas. http://www.exploratorium.edu/exhibits/espanol/changingill/index.html El museo virtual de Escher Observa las obras del pintor Maurits Cornelius Escher. http://nucleogestion.8m.com/HALL.HTM Internet Field Trip: Microscopes Internet Links Scanning Electron Microscope A scanning electron microscope is an amazing tool for seeing the microscopic world. Find out how this incredible device works! http://www.mos.org/sln/sem/ Microscopio virtual Aprende cómo fueron inventados los microscopios y mira algunas fotos microscópicas. http://personales.mundivia.es/mggalvez/micro1.htm Internet Field Trip: Sound Internet Links The Soundry What are sound waves? How fast does sound travel? What is the Doppler effect? Visit the Soundry to find out! http://library.thinkquest.org/19537/ Sound FX Page This Web site has lots of bells and whistles—and other neat sounds. Hear chimes, grandfather clocks, and more at this unusual site. http://www.vionline.com/sound.html#INDEX Vocales vocalizadas ¿Qué es el sonido? Averígualo visitando este sitio. http://www.exploratorium.edu/exhibits/espanol/vocal_vowels/index.html Internet Field Trip: Sound Recording Internet Links How Tape Recorders Work Visit this Web site to learn how a tape recorder captures sound. http://www.howstuffworks.com/cassette.htm How Compact Discs (CDs) Work Do you want to know how tape recorders and CD players work? This Web site explains how! http://www.howstuffworks.com/cd.htm