If you don’t remember what Newton’s Cradle is, it “demonstrates conservation of momentum and energy via a series of swinging spheres.”
In other words, if you swing a ball at one end, the ball at the other end will absorb that energy through the other balls and then swing out as well.
So, anyway, these adorable kittehs discover a Newton’s Cradle and begin be exploring the resulting physics, but end by trying to destroy them.
ADORABLE. Except, you know, to the toy. It probably wishes the kittens left it alone.