They both cause a lot of trouble in the ocean? It's unhealthy to be hit on the head with either one? I'd do my best to whack either one away from me with a golf club? All true. But also, they both have surfaces designed to take advantage of physics.
Oh, there are so many reasons that sharks are like golf balls. They're both tough to film, but they both get an disproportional amount of time on television, and both are so much more fun to watch if, somehow, there is blood involved. The connections go on and on. But only one connection has to do with physics.
Golf balls, if you've noticed, have dimpled outsides. This allows them to fly faster. A smooth ball clears a path through the air, leaving a clear, wide wake of low-pressure air behind it. This low pressure air sucks the golf ball backwards, slowing it down. The little divots in golf balls create pockets of turbulence that cause air to swirl around the ball. They hug the back curve of it, pressing close and creating a smaller wake. This smaller wake does less to hold the ball back and lets it fly farther.
Sharks look smooth, but actually, they're covered with tiny curving spikes called dermal denticles. Denticles resemble small, flattened coat hooks, all on top of each other and all curving towards the back of the shark. It's recently been found that they do the same things that golf ball dimples do - break up the wake and let the shark move through the water faster and with less energy. They are masters of fluid dynamics.
Also, sharks are like golf balls because - when people are handling either, it's considered bad form to make loud noises.
If you'd like to learn more about sharks, check out shark week on our show. We talk to a shark expert who has great footage of shark research, discuss our favorite shark movies, and argue about the genre of Jaws.
Top Image: Tanaka Juuyoh
Via Physics Central.