The resistance to relative motion of two bodies in contact with ...

[tsand2]

The resistance to relative motion of two bodies in contact with each other is called __________.
 Fill in the blank(s) with correct word

Question 2

Fusion reactors like the Tokomak shown here would be an ideal source of energy that do not suffer from the disadvantages of fission reactors. Why is nuclear fission much more practical as an energy source than nuclear fusion?
 a. Because radioactive nuclei are available as a fuel for fission, but no fuel for nuclear fusion is available.
  b. A chain reaction drives nuclear fission, but sustaining nuclear fusion is much more difficult.
  c. Nuclear fusion has never been demonstrated.
  d. The lower atomic masses of the fusion fuels limit their energy output.
  e. The high temperatures needed for fusion make fusion reactors far too dangerous.

[Anton]

Answer to Question 1

friction force

Answer to Question 2

b

[tsand2]

Excellent

[bulacsom]

Thanks for the timely response, appreciate it