Question

the pendulum on a grandfather clock swings from side to side once every second. If the length of the pendulum is 3 feet and the angle through which it swings is 10 degrees, how far does the tip of the pendulum travel in 1 second?

Answer 1

Check the picture below

thus $\bf s=\cfrac{r\theta\pi }{180}\qquad \begin{cases} s=\textit{arc's length}\\ r=radius\\ \theta=\textit{angle in degrees}\\ ----------\\ r=3\\ \theta=10 \end{cases}\implies s=\cfrac{3\cdot 10\cdot \pi }{180}$