In a genius marketing move, helmet company Shark Helmets made a very real Newton’s Cradle using people. Hanging upside down, five bikers wearing regular helmets recreated the physics of the popular science toy by banging their helmets against each other.

When the first biker is dropped, the kinetic energy traverses across the rest until the energy sends the last biker swinging up into the air. 

But here’s the point. Afterwards, they all don Shark Helmets. The Sharks absorb so much shock, the experiment no longer works. Now that’s advertising in action.