The leading explanation for the existence of spiral arms are: Group of answer choices shock waves from cyclic supernovae explosions. shock wave from the quasar-like eruption of the galactic core. tidal streams of small galaxies being torn up by our monster Galaxy. passages of massive globular clusters through the galactic plane. passages of spiral density waves through the interstellar medium.

Arrange the images in order to show how lake-effect snow occurs.

When measuring volume, why is it important to use the correct tools and units to attain the greatest accuracy? use specific examples from the lab to support your answer. (5 points)

Aparticle of mass m is placed in a one-dimensional box of length l. the box is so small that the particle’s motion is relativistic, so that e p2/2m is not valid. (a) derive an expression for the energy levels of the particle using the relativistic energy–momentum relation and the quantization of momentum that derives from connement. (b) if the particle is an electron in a box of length l 1.00 1012 m, nd its lowest possible kinetic energy. by what percent is the nonrelativistic formula for the energy in error?