An open freight car rolls friction-free along a horizontal track ...

[jCorn1234]

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.

[ebenov]

Answer to Question 1

Answer: B

Answer to Question 2

C

[jCorn1234]

Thanks for the timely response, appreciate it

[bigcheese9]

YES! Correct, THANKS for helping me on my review