You overhear two students discussing the topic of Doppler shift.
Student 1: Since Betelgeuse is a red star, it must be going away from us, and since Rigel is a blue star it must be coming toward us.
Student 2:
I disagree, the color of the star does not tell you if it is moving. You have to look at the shift in wavelength of the lines in the star's absorption spectrum to determine whether
it's moving toward or away from you.
Do you agree or disagree with either or both of the students?

The atoms in a sidewalk on a hot summer day are vibrating the atoms in the sidewalk on a freezing day in winter. a. more rapidly than b. more slowly than c. at the same speed as

A250-n box is at rest on a frictionless horizotal floor. then a person shoves the box with a non-zero force of magnitude p. which statement best describes the relationship betweeen p and the motion of the box after it was shoved? -the box will not move when p< 250n but otherwise will accelerate at a constant rate that is directly proportional to p - the box will begin moving at a speed that is directly proportional to p, then will gradually slow to a halt -the box will move with constant velocity at a speed that is directly proportional to p -box will accelerate across the floor at a constant rate that is directly proportional to p

The least penetrating form of radiation is