(OT) US Press - growing a spine?

illconsidered — Tue, 19 Feb 2013 12:09:48 +0000

This is not directly climate related, but it does pertain to the media and its abject failure to take its responsibilities towards democracy more seriously. Via The Huffington Post, I read these strong words from an angry press towards a secretive Whitehouse Administration:

Speaking on behalf of the White House Correspondents Association, I can say a broad cross section of our members from print, radio, online and TV have today expressed extreme frustration to me about having absolutely no access to the President of the United States this entire weekend. There is a very simple but important principle we will continue to fight for today and in the days ahead: transparency.

Hear hear! Democracy requires transparent government. So what is it the Obama administration is hiding? The memos explaining the remotely piloted drone execution policies? The nature and reach of the global network of CIA "black sites"? The extent of the dragnet email and internet surveillance of the entire citizenry?

Uh, no. They are upset they can't watch him play golf with Tiger Woods this weekend. Words fail....

illconsidered Tue, 02/19/2013 - 07:09

Weekend Diversion: The Physics of Happy Gilmore

esiegel — Sat, 15 Sep 2012 17:35:17 +0000

Weekend Diversion: The Physics of Happy Gilmore

"What a shot by Happy Gilmore! <aside> Who the hell is Happy Gilmore?" -Announcer, from Happy Gilmore

As I prepare to write this, it occurs to me that some of you may not have seen the greatest* movie of all time, Happy Gilmore. The movie begins with a montage of Happy's disastrous and violent childhood, where he -- a wannabe hockey player -- is raised by his very sweet grandma (played by Frances Bay, RIP one year today) while the you're treated to the Lynyrd Skynyrd classic,

Tuesday's Gone.

Happy has an amazingly powerful slap shot, which isn't quite enough to land him with a minor league hockey team, but -- combined with an unorthodox running start -- is enough to make him the longest-driving golfer in the world.

Image credit: Universal Pictures, Frank Coraci, and Adam Sandler et al.

Now, I was intrigued by this, because not only is such a swing actually legal in professional golf (although not so much if you're drunk in Nova Scotia), but according to the laws of physics, it should actually make the ball go significantly farther!

Let me explain.

Image credit: Harold "Doc" Edgerton, of golfer Denny Shute in 1938.

When you collide an object like a swung golf club with a stationary golf ball, there are really only three things that are going to impact how fast the ball comes off of the club head.

One, of course, is the speed of the club head relative to the ball. A golfer that can get the club head traveling at 100 miles-per-hour upon impact with the ball is going to have a distinct advantage over one that can only get it up to 95 miles-per-hour.

Image credit: John Darling of Power Golf Instruction.

The second is also unsurprising: it's hitting the ball in the "sweet spot" of the club head. The reason for this is pretty straightforward: you want to transfer as much energy from the club to the ball as possible. If you strike the ball away from the sweet spot (or more technically, the center of percussion), you're going to create oscillatory vibrations in the club, which you'll be able to feel in your hands. (If you've ever felt pain in your hands after swinging a baseball bat and making lousy contact, this is the same effect.) That's energy that's being transferred up the shaft of the club instead of into the ball, and that's going to hurt your ball's distance.

So swing the club head as fast as possible, aim for the sweet spot, and use the heaviest club head possible.

Image credit: Callaway golf.

There's usually a trade-off between the speed of the club head and the mass of a club head; there's a limit to how fast we can swing a heavy weight positioned at the end of a long rod. But the heavier and faster we can go, the more we're going to deform the golf ball, and the faster the ball's going to leave the club head.

For example...

Image credit: K. Arakawa, T. Mada, H. Komatsu, T. Shimizu, M. Satou, K. Takehara & G. Etoh, 2007.

Here's a collision (above) between a 45-gram golf ball and a 200-gram club head moving at 136 miles-per-hour relative to one another. That's some intense deformation of the golf ball!

But it's not nearly as spectacular as this (alleged) 150 mile-per-hour collision between a 45-gram golf ball and a 50 pound steel plate!

But I wouldn't be surprised if this was faster than 150 mph.

What's the big difference? In addition to speed, the 50-pound steel plate means you have something of virtually infinite mass (in comparison to the ball) colliding with it, as opposed to something that only outweighs it (the club head) by a factor of 3 or 4.

In a perfectly elastic collision, striking a small mass object with a much larger massed object causes the small one to move off at twice the initial speed.

Image credit: John D. Norton of the University of Pittsburgh.

A club head is only about four times the mass of the ball, and although both ball and club technology have improved, they're still not (and never will be) perfectly elastic. If you can swing a club head at 100 miles-per-hour, you can get the golf ball moving, realistically, at about 150 miles-per-hour. (If the collision were ideally elastic, you might be able to get up to about 180 miles-per-hour.)

So, according to physics, if you can use a running start to get an extra few miles-per-hour (let's say 5 miles-per-hour) onto your club head speed, that should translate to an extra 8 miles-per-hour for the initial speed of your ball. What does that mean for distance?

Image credit: Trajectoware Drive.

Again, according to realistic physics, we're talking maybe an extra 10% longer off the tee, which isn't too shabby!

When I first realized this, I figured that -- based on how hard it is to actually hit a golf ball decently at all -- taking a running start was simply too hard. You'd miss the sweet spot or the ball entirely, and so this was out of the question. But then it was pointed out to me that some golfers can, in fact, do some amazing things with a golf ball.

So maybe this was reasonable after all! After all, if it isn't against the rules, and it could add an extra 10% to your drive, who wouldn't want to be an extra 30 yards closer to the hole?

According to simple physics, it should be true that a running start plus a perfect swing should get you closer to the hole than simply a stationary swing.

That middle photo is another by Doc Edgerton, of golf legend Bobby Jones.

So what happens when you take one of the top players in the world and have them drive the ball using the Happy Gilmore-style swing? Can they still hit the sweet spot of the ball? See for yourself, courtesy of Sport Science. (Skip to 3:13 to watch the action if you're impatient.)

It really is a thing of beauty, and it's always amazing when the theory agrees so well with the experimental results! I don't golf, but if I did, there's no way I wouldn't try for the Happy Gilmore advantage. I would love to see someone give it a shot under tournament conditions, because it really does make a difference. Just make sure you get plenty of practice and wear cleats, because no one wants to wind up looking like this guy!

Hope you enjoyed the physics of Happy Gilmore, and here's wishing you a great weekend!

* -- I was 17 years old when Happy Gilmore was released, and I continue to love this movie to this very day. It is by no stretch of the imagination a fine film, but it strikes that rare, golden balance between absurdity, immature humor, and heart. If you've had the good fortune to spend lots of time with me during my late teens or 20s, you were probably forced to watch it with me at some point. My insincerest apologies to you if that was the case, because that movie is awesome, you jackass!

esiegel Sat, 09/15/2012 - 13:35

Tiger Woods is a golfer

razib — Tue, 01 Dec 2009 13:20:11 +0000

Tiger Woods is a golfer

Why Tiger's endorsement empire is safe:

And as indiscretions go, this is not Michael Vick, say sports marketers. This is not Michael Phelps. This is not Kobe Bryant. Not yet, anyway.

"I'm convinced that this will not cause the end of Tiger Woods Inc. as we know it," said Paul Swangard, managing director of the University of Oregon's Warsaw Sports Marketing Center.

Probably Woods will still make gajillions of dollars in endorsements. Vick and Bryant's transgressions were much more serious. But are professional golfers graded on the same curve as NBA or NFL athletes? I'm skeptical.

razib Tue, 12/01/2009 - 08:20