Two forces $P$ and $Q$ act on a metre rule, as illustrated. The metre rule is pivoted at one end. The rule begins to turn in a clockwise direction. Which statement is correct?
- A$P$ equals $Q$
- B$P$ is less than $Q$
- C$(P \times a)$ is equal to $(Q \times b)$
- D$(P \times a)$ is greater than $(Q \times (a + b))$