A loudspeaker aperture 12 inches in diameter is putting out 5 watts of acoustic power at a frequency around 5,000 cycles per second. Estimate the amplitude of motion of the air at the Aperture. Let M 1 be the mass within a volume of one cubic centimeter, in atmospheric air. Let M 2 be the mass within that same volume on minute later. A star like the Sun is just about invisible to the naked eye if it is 50 light years away.
All industrial aluminum is refined electrolytically.
A stray meteorite is on a circular orbit of radius twice that of the Earth's orbit. Predict its temperature. A television transmitter is radiating 10 kilowatts from its antenna. Compare the energy stored in wave motion in the world's oceans with the daily influx of energy from the Sun. Estimate the amplitude of vibration of your ear drum, at audio frequency, which arises from ordinary thermal agitation, or Brownian motion.