A simple pendulum has a length $l = 2.45$ m. Find its period of oscillation. The acceleration due to gravity is $g = 9.8$ m/s².
The period of a simple pendulum:
$$T = 2\pi \sqrt{\frac{l}{g}} = 2\pi \sqrt{\frac{2.45}{9.8}} = 2\pi \sqrt{0.25} = 2\pi \cdot 0.5 = \pi \approx 3.14 \text{ s}$$
$T \approx 3.14$ s