Making Sport of Physics

Ronaldo’s PK: Black Magic or Simple Physics?

Did you see the crazy penalty kick Real Madrid‘s Cristiano Ronaldo let loose against Paris Saint-German this past Valentine’s Day?  In the 45th minute, Ronaldo blasted the ball into the left side of the net.  What made people’s jaws drop was what happened to the ball just prior to Ronaldo’s famous right boot making contact with the ball.  The ball popped off the turf!  You can see the video here where “black magic” is referred to.

I did a frame-by-frame analysis for i News in the UK.  There was, of course, no black magic involved!  Check out the images below (click on image for a larger view).

As Ronaldo planted his left boot, a pressure wave was initiated in the turf.  A crinkle was all it took to get the ball to hop off the turf about a centimeter.  Click here for more details in the story by Will Magee.  Getting ball off the turf prior to kicking saved a little energy loss from friction between the ball and turf.  Hard to stop that shot!

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Curling is AWESOME!

StarTalk‘s Playing with Science aired an episode on curling yesterday evening.  I had a LOT of fun doing that episode!  Curling is one, cool spot.  There is plenty of fascinating physics and an unanswered question or two.  Check out the show via the link below.

My plan was to post the above show’s link last night, but the shooting in Florida took my thoughts elsewhere.

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How many slaughtered will it take?

My cousin notified me of yesterday’s atrocity in southern Florida.  Broward County?  That’s where my sister’s family lives and where her kids go to school.  I called my sister.  “Is that [my nephew]’s school?”  “No.  His school is in the neighboring district.”  Marjory Stoneman Douglas High School in Parkland is eight miles from my sister’s house.  She described to me scenes of roads packed with cars as parents raced to their kids.  Friends of my sister had a son in that school yesterday.


What I described above is as close as I’ve ever been to a school shooting (I did know a student at Virginia Tech in 2007).  I know what’s it like to lose a child.  I know what it’s like for a moral monster to steal half my children’s childhoods from me.  I know what’s it like to be told a friend was murdered with a gun.  I’ve known parents who watched a state trooper pull his car in their driveway and inform them that their child was killed in a car wreck.  My guess is that anyone reading this will share some or all of what I’ve experienced.  I suspect there is a reader or two who has been directly affected by a school shooting.  I don’t know what it’s like to send one of my daughters to school and never see her alive again.  I hope I never experience such a horror.  Any tragedy in my life pales in comparison to a parent sending a child off to school, only to have that child be murdered.

How many dead children are enough?  How many people, simply going about their lives, working, playing, etc have to be slaughtered before the needle of sense moves in my country?  When do we in the US have our Dunblane?  When do we have our Port ArthurSandy Hook saw 27 murdered, but that didn’t change anything.  Last October, 58 people were shot dead in Las Vegas, but that didn’t change anything.  I couldn’t possibly list all the mass shootings in the US because I have to feed my girls dinner in a couple hours.  I read yesterday (click here) that we’ve now had four shootings at middle and high schools in 2018.  Yesterday was just the 45th day of the year.  Children are taken through “shooter in the building” drills in schools in present day America.  My girls never did that during their school year in England.

We are learning about all kinds of mental issues associated with the loathsome individual who destroyed countless lives yesterday.  What astounds me is that many of the same people who so ferociously defend our “right” to own and use an AR-15 or a Bushmaster or some other military weapon simultaneously rail against universal health care and more money for mental illness treatment.  There are plenty of people with mental issues in countries that have serious gun restrictions.  This problems isn’t confined to mental issues.  The ease of obtaining a weapon that can end many lives in a short time is obscene.

Like many other politicians, President Trump offered “prayers and condolences” yesterday.  No matter how good the intentions or how warmed people may be to receive “prayers and condolences,” I have to ask, when is that bullshit going to end?  When are people going to embrace reality and actually DO something in the here and now?  Will it take a politician’s kid being murdered to get something done?  What if a lobbyist’s child gets shot at school?  Or a celebrity’s kid?  Does the death count have to reach triple figures in a massacre to make us think that, perhaps, we don’t need assault rifles?  Are we going to go nuts in the other direction and have guards armed to the teeth walking down every corridor in every school?  I need not insult my readers by detailing the absurdity of that scenario.

If by chance anyone is reading this that has been affected by a school shooting, please know that I’m filled with sadness and anger over what happened yesterday.  Kids in Parkland are not alive today because of a “blessing” or “luck.”  They are alive because they were not in the wrong place at the wrong time.  The power to take a life, many lives in fact, is too easy to acquire in my country.  Four shootings in middle and high schools in just 45 days so far this year.  What’s in store for the next week-and-a-half?

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Winter Olympics! Let’s Talk Figure Skating!

Tonight’s episode of StarTalk‘s Playing with Science will get you ready for the Winter Olympics, which begins this Friday in PyeongChang, South Korea.  We talked figure skating, which is so many people’s favorite event come Winter Olympics time.  A very special guest is on the show, Olympic Medalist Sasha Cohen.  I have such wonderful memories watching her compete in the figure skating competition at the 2006 Winter Olympics in Turin, Italy.  My older daughter, Emily, and I rooted Sasha on like crazy.  Emily wasn’t quite two-and-a-half at the time, but she got a great introduction to Olympic skating.  My younger daughter, Abby, was born less than a month later.  I recall patting my wife’s belly and telling Abby to root for Sasha while she skated.  Abby doesn’t remember that!  Sasha took home the silver.

The link for tonight’s show is given below.  Also on the show is Jackie Wong, who I thoroughly enjoyed talking to.  He hosts the podcast Ice Talk.   Check it out!

The video producer at StarTalk was kind enough to send me a screen capture when I was posing a question to Sasha Cohen (click on the image below for a larger view).

I actually had to leave the show earlier than I wanted.  I had to drive across town and give a keynote address at Randolph College.  No need to have a tie on otherwise!
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Physics of the Quad Cork 1800

I worked on a piece for WIRED Magazine that appears in its February issue.  Billy Morgan successfully executed the famed snowboarding trick known as the quad cork 1800.  I analyzed the trick from start to finish and WIRED has a phenomenal two-page photographic spread that shows the entire trick from stroboscopic images.  I calculated several numbers, from launch speed to landing force.  Check out the nice spread on pages 20-21 (volume 26, issue 2).  I worked with Sophia Chen on the piece and she did a great job putting it all together!  Click here for a sneak peak.

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Great fun giving my talk!

I thoroughly enjoyed giving the keynote address at Randolph College last Saturday for the United States Association for Young Physicists Tournament (USAYPT).  My audience got to hear about my Tour de France research and my research on World Cup soccer balls.  It was my first chance to speak about the Telstar 18, which will be used in Russian during this summer’s World Cup.  My friend and colleague Peter Sheldon took the photo below as I was on stage giving my talk (click on image for a larger view).

During talks and media experiences, I like to sell the virtues of my college, Lynchburg College.  I’m always looking for new students to join us at Lynchburg College, major in physics, and contribute to my research.  Students have always played a central role in my sports research.  I was treated very well at Randolph College and I’m happy give that school a shout-out here.  Check out what Peter has going on in the Department of Physics there!

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Martial Arts Repeat

Tonight’s Playing with Science episode is a repeat, but it happens to be the fan favorite episode for 2017 (click here for the poll results).  If you missed the martial arts episode, check it out!

I’m thrilled fans of the show voted this episode their favorite Playing with Science episode.  I’m in the process of completing my Krav Maga book.  I hope it’ll be available early in 2019.

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Keynote Talk this Saturday

I was extremely flattered to be asked to give the keynote address for the United States Association for Young Physicists Tournament (USAYPT) at Randolph College here in Lynchburg.  My talk will be this coming Saturday, 27 January 2018, at 4:15 pm in Smith Hall Theatre.  A poster appears below (click on image for a larger view).

This will be my first talk of the year, and it will be the first talk in which I discuss the Telstar 18 soccer ball, which will be used in Russia for this year’s World Cup.  I look forward to meeting the talented high school students at the tournament!

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Playing with Science Mix

StarTalk‘s Playing with Science put together a nice mix from the first two seasons.  I get to chime in on the show.  Click the link below for last night’s episode.

It was a lot of fun working with Playing with Science in 2017!  Who knows what’s in store for this year with the Winter Olympics and World Cup …?

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Physics and Psychology Aid Callahan’s Punt Return TD!

The Chicago Bears finished a rather dreadful season with a loss to the Minnesota Vikings today, 23-10.  The Bears did have a fun play that I got to analyze for TuneIn‘s Ho Huddle.  With just over six minutes left in the first half, the Vikings faced a 4th and 9 at their own 16-yard line.  Vikings’ punter Ryan Quigley (#4) punted the ball from Minnesota’s 7-yard line (click on image below for a larger view).

You can see in the above screen capture that Quigley was right on the 7-yard line when the ball left his right shoe.  The ball was punted at almost 60 mph and over 60 degrees to the horizontal.  For an incredibly short amount of time, the force between shoe and ball on a good punt can be over 1000 pounds.  The punted ball traveled 53 yards and had a hang time of 4.24 seconds.

The problem for the Vikings was that the Bears’ Tarik Cohen (#29) played the perfect decoy.  He was on the right side of the field and acted as if he was going to catch Quigley’s punt.  But Bryce Callahan (#37) was on the left side of the field and caught the punt while sliding on his own 40-yard line (click on image below for a larger view).

Look at Cohen with his arms out like he’s about to catch the punt!  The Vikings’ Jayron Kearse (#27) is running full speed at Cohen while Callahan has just caught the punt.  The screen capture below shows when Callahan got up after his slide (click on image for a larger view).

You can see the purple blurs heading toward Cohen!  I couldn’t tell from the video I watched, but Quigley should have been yelling at his teammates, telling them where his punt was headed.  Even though the Vikings were at home, the noise level could have been in the 70 dB – 100 dB range, which corresponds to the sound a vacuum cleaner makes all the way up to what a busy subway sounds like.  Quigley’s teammates down the field probably wouldn’t have heard him if he was yelling.

Callahan could get up after his slide and run because the NFL doesn’t use college football rules.  The screen capture below shows that Callahan had many blockers in front of him (click on image for a larger view).

The Vikings are headed to the right while Callahan is preparing to run down the left side of the field.  Cohen did such a good job selling the fake that Kearse nearly ran into Cohen and had to veer off to Cohen’s left upon realizing that Cohen didn’t have the ball.  Check out the screen capture below, which shows five Vikings near Cohen, all realizing too late that they ran after the wrong player (click on image for a larger view).

Meanwhile, Callahan was hitting a top speed of 19 mph in Vikings’ territory (click on image below for a larger view).

Callahan crossed the goal line at about 16 mph, having slowed a little to celebrate (click on image below for a larger view).

A lot of great physics for sure, but psychology had the Vikings off course and chasing the wrong Bear!  The Bears finished 5-11 this year, but left me with a fun play to analyze before bringing their season to a close.

Chuck Nice of Playing with Science joined me on today’s segment.  As he always does, Chuck set up the play really well before tossing it over to me for the nerdy stuff.  Click here for our segment.  The NFL regular season finished up today, but like the 13-3 Vikings, we football fans are anxious for the playoffs to begin!

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