Chapter 11 Simple Harmonic Motion. Chapter 11. Hooke’s Law. One type of periodic motion is the motion of a mass attached to a spring. The direction of the force acting on the mass ( F elastic ) is always opposite the direction of the mass’s displacement from equilibrium ( x = 0).
Felastic = –kx
spring force = –(spring constant displacement)
Section 3 Properties of WavesWave Motion
v = f
The most famous and conspicuous supernova remnant. The Crab Nebula is the centuries-old wreckage of a stellar explosion, or supernova, first noted by Chinese astronomers on July 4, 1054, and that reached a peak magnitude of -6 (about four times brighter than Venus). According to the Chinese records, it was visible in daylight for 23 days and in the night sky to the unaided eye for 653 days. Petroglyphs found in Navaho Canyon and White Mesa (both Arizona) and in the Chaco Canyon National Park (New Mexico) appear to be depictions of the event by Anasazi Indian artists. The Crab Nebula lies about 6,300 light-years away in the constellation Taurus, measures roughly 10 light-years across, and is expanding at an average speed of 1,800 km/s. Surprisingly, its expansion rate seems to be accelerating, driven by radiation from the central pulsar. Its luminosity at visible wavelengths exceeds 1,000 times that of the Sun