## College Physics (4th Edition)

The period of the vibration is $13.5~s$
When the person swings at the end of the rope, the person is swinging like a pendulum. We can find the period of the vibration: $T = 2\pi~\sqrt{\frac{L}{g}}$ $T = 2\pi~\sqrt{\frac{45~m}{9.80~m/s^2}}$ $T = 13.5~s$ The period of the vibration is $13.5~s$.