Perpetual motion machines without an additional energy input ...

[RODY.ELKHALIL]

Perpetual motion machines without an additional energy input cannot exist because
 
  A) energy cannot be created or destroyed.
  B) in any energy conversion, some energy is lost.
  C) energy cannot be converted from one form to another.
  D) kinetic energy requires an input of light energy.

Question 2

In nuclear power plants in the United States, near-pure water functions as
 
  A) a moderator, heating up as it slows down neutrons, which triggers additional fission reactions.
  B) a moderator, cooling down as it slows down neutrons that could cause fusion reactions.
  C) an inhibitor, preventing neutrons from heating up and causing fusion reactions.
  D) an inhibitor, preventing neutrons from cooling down and stopping the fission reactions.

[al]

Answer to Question 1

B

Answer to Question 2

A