Question

how does inertia helps a cat to get dry

Answer 1

As we see, when a cat gets wet, it typically dries itself off by shaking vigorously. The reason behind is that when the cat shakes to-and-fro rapidly, it's furs move in the same way but when the furs move away from their position continuously, the water droplets on the furs remain in the same place due to inertia of rest. Hence, the water droplets get detached from the fur of the cat and it gets dried.