The fixed edges of a string are 45 cm apart and when plucked the string
vibrates with a fundamental frequency of 377 Hz. If the desired
fundamental frequency for the string is 627 Hz, how far apart should the
fixed edges be?

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What is the increase in density of a medium due to wave travel?

Ascientist notices that an oil slick floating on water when viewed from above has many different colors reflecting off the surface, making it look rainbow-like (an effect known as iridescence). she aims a spectrometer at a particular spot and measures the wavelength to be 750 nm (in air). the index of refraction of water is 1.3