Sunday, May 27, 2018

Does the wake drive the boat?

In one of his talks, the late Wayne Dyer, a famous motivational speaker, declared: "The wake does not drive the boat." What he meant was that, as we age, we develop narratives about how the misfortunes of our pasts limit our present and future choices. He says these narratives are false excuses since our pasts are merely trailing phenomena like wakes (the water pushed out behind sailing ships) and cannot control where we are going. After all, the wake does not drive the boat, and our pasts don't control where we go. In this video, begin at about 15:45, listen for a minute, and you'll hear his claim.

I was immediately afflicted with the goosebumps I get when I am skeptically curious. Is that true? The wake doesn't drive the boat?

I thought of a question that appeared at the end of James Carroll's recent novel The Cloister. "You are towing a large barge on a hawser...Your main engine suddenly fails. What is the greatest danger?" The character, taking the boating licensing examination, answered: "Obviously, 'The tow will overrun tug.' Ten thousand gross tons of barge weight crushing the engineless tugboat—there's the danger."

We know that this happens with cars and trucks, too. I once witnessed a similar kind of accident. A truck driving in front of me had a mechanical failure in which its trailer detached from the cab. The driver may or may not have noticed it, but in any case would have had no way to stop the trailer, which continued rolling along with its own momentum, at roughly the same direction and speed it had had at the time of the detachment, until the road curved slightly and the trailer was stopped by its collision with a utility pole. But, I wonder, for boats specifically, is this behavior simply due to the law of inertia — an object in motion stays in motion, unless you can brake — or, in boating, does the water wake provide an additional push to the boat?

If it does not, how, then, does the sport of "wakesurfing" work? The Wikipedia page for wakesurfing includes this video of a surfer following behind a boat by riding the wake without holding on to any rope.

In 2013, Peter Lynch wrote "The science behind the ripples and wakes in water." In 2014, Simen Ådnøy Ellingsen said that "[a]bout half of the fuel burned by a ship goes to making these wave patterns," energy that is typically wasted, and that there is "resistance caused by the wake." Resistance, not assistance, and not zero impact, either. Similar topics were discussed on Stack Exchange in 2015, "Water waves in the wake of a boat." These articles and diagrams may contain the answer, but they are difficult for me to interpret.

Do you know the answer? Was Wayne Dyer's analogy correct? Post a comment!

At the top of this post: Public domain photo of the wake from a U.S. Naval Special Warfare Combatant Craft retrieved from Wikimedia Commons.

1 comment:

  1. I appreciate what Wayne is trying to say, but I wouldn't dare comment on the physics of wake water behind a boat. I like his message that our lives are constant creations and how we interpret our life lessons have a big effect on our happiness. I just finished reading 'Super Brain' by Deepak Chopra and Rudolph Tanzi and enjoyed the way they communicated that powerful idea also using physics. I recommend it if you haven't already read it.

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