Author Question: Spiral arms are obviouseasily-seen featuresbecause they contain ____. a. dense molecular clouds ... (Read 34 times)

Zulu123 · **on:** Jul 27, 2018

Spiral arms are obviouseasily-seen featuresbecause they contain ____.

a. dense molecular clouds
b. atomic hydrogen clouds
c. sun-like stars
d. OB associations
e. supernovae

Question 2

The second postulate of special relativity states that ____.

a. observers cannot detect their uniform motion except relative to other objects
b. observers cannot distinguish locally between inertial forces and uniform gravitational forces due to acceleration and the presence of a massive body
c. the laws of physics are the same for all observers regardless of their motion as long as their speed is constant
d. the speed of light is constant and will be the same for all observers independent of their motion relative to the light source
e. the acceleration of an object is proportional to the applied force and inversely proportional to its mass