Question 8
In activity 2 the wooden strip was tightened step by step without moving the balance from where it was attached. The force needed to turn it rose from 2 N to 5 N and then to 9 N. What does this confirm?
The right answer is the one marked above.
The moment of a force depends on the magnitude of the force. The balance stayed at the same point, so the perpendicular distance was constant; the force was the only thing that changed.
It is activity 3 that shows the dependence on perpendicular distance. Since force was the only quantity varied here, force is the only thing this activity can conclude about.