Author Question: An open freight car rolls friction-free along a horizontal track in vertically pouring rain. As ... (Read 47 times)

jCorn1234 · **on:** Jul 29, 2018

An open freight car rolls friction-free along a horizontal track in vertically pouring rain. As water accumulates in the car, its speed

A) increases.
B) decreases.
C) doesn't change.

Question 2

Which of the following is considered by scientists to be physically real, but yet is not made of atoms or of other material particles such as protons, electrons, etc.?

A) the air
B) neutron stars
C) electromagnetic fields
D) the ether
E) Nonsense--we have known since Democritus that everything is made only of atoms and empty space.