Potent Physics of Hitting a Baseball Keys to Swing Smarter NOT Harder

Physics of Hitting a Baseball

The physics of hitting a baseball is NOT for the faint of brain, however some really fantastic "Did You Knows" have come out of the brilliant study and authorship of two baseball books, "The Physics of Baseball" & "Why a Curveball Curves," by Robert Adair, a 83-year-old sterling professor emeritus of physics at Yale University.

He's answered cool questions us baseball Neanderthals have about hitting, like:

  • Why is putting backspin on the ball so critical to a batter?
  • Which hit pitch goes further, a curveball or fastball?
  • When you pull a ball, does it really go farther than hitting it to centerfield or the opposite way?
  • Does a lighter bat help to generate more bat speed, therefore the batted ball traveling farther?

I'm sure you have your own assumptions to these questions, and we'll apply Robert Adair's analysis and findings from the American Journal of Physics (AIP.com) to find the real truth about the physics of hitting a baseball.

First, watch this informative 2.5 minute video from the Science Channel titled, "The Physics of Baseball - Flight of the Ball"

Baseball has seen brilliant minds, such as Robert Adair, who have a passion for the game and have applied disciplines like physics, philosophy, math (Sabermetrics), and science to angles in the sport we didn't know existed. A prime example is Ted Williams's swing gospel, The Science of Hitting.

After viewing the above video, our brain should be primed better in understanding the physics of hitting a baseball...

Why is putting backspin on the ball so critical to a batter?
A big part of swing smarter NOT harder is the Down & Through method of the baseball swing, which is a precise combination of bringing the knob DOWN to the pitched ball (shortest distance between two points), and taking the barrel THROUGH the contact point like a Martial Artist breaks boards and bricks...creating a powerful backspin, resulting in further flight path.

Gravity, drag force, and Magnus Force are the three variables from the video, acting on a baseball determining its flight. Backspin creates an invisible Magnus Force underneath the ball propelling it up-wards and out-wards, making the ball work for us, and NOT the other way around.

There are two other linear batted ball spins related to the physics of hitting a baseball; top spin and knuckleball spin. Top spin causes the ball to sink...and knuckleball spin is the result of the hitter getting the ball squarely, sending it fluttering into the outfield like a dancing butterfly.

Which hit pitch goes further, curveball or fastball?
I learned something new on this one, definitive information harvested from AIP.com's analytics reveal,

"An optimally hit curveball will travel farther than an optimally hit fastball due to increased lift during flight."

How about...?

When you pull a ball, does it really go farther than hitting it to centerfield or the opposite way?
From Robert Adair's findings, he discovered a hitter can hit the baseball further by pulling it rather than going up the middle or the other way. I suspect because the contact point is closer to the body's center as opposed to an outside pitch being farther away.

The physics of hitting a baseball this way also depends on hitting the ball with the proper inside-out swing approach...NOT putting a bending hook spin on the baseball.

This does NOT mean every hitter should be pulling the ball to see how far they can hit it however...this would be a pitcher's wet dream, if every hitter tried this every at bat. We must be a smarter balanced hitter, taking what the pitcher gives us, and spraying the ball to all fields.

Does a lighter bat help to generate more bat speed, therefore the batted ball traveling farther?
Robert Adair has done quite a bit of work on looking at the hitter's weight and distance they can hit the ball recently...the result, surprise, surprise, the heavier a hitter is, the farther they can hit the ball.

That's why Shane Victorino of the Philadelphia Phillies will never be able to hit the ball farther than an Albert Pujols type of hitter, it's the difference between 180 pounds and 230, respectively.

Also a part of the physics of hitting a baseball, inertia is the measure of how lazy "stuff" is...

"Inertia is the resistance of an object to a change in its state of motion." -Wikipedia

You can replace the word "resistance" above with "laziness."

In other words, objects in motion tend to stay in motion until acted upon by another force. On the flip side, objects at rest tend to stay at rest until something changes its state, which describes our kids sometimes glued to their PSP's, Wii's, or PS3's, that "force" acting on them being mom and dad;-)

The formula for inertia is: Force = Mass times Acceleration (F = ma). So, the faster we can accelerate a heavier bat, the better the Force put on the baseball, and the farther it'll go.

So, as inertia relates to the physics of hitting a baseball...

If we swing too light of a bat (less mass), and swing it really fast, we won't maximize our Force output; likewise for if we use too heavy a bat and cannot accelerate it very quickly. We have to entertain a happy medium in weight of the bat (mass) and the speed to which we swing it.

One "X" factor is to NOT sacrifice swing tempo for too much acceleration (over swinging), dampening our production. By not allowing the proper points to line up in our swing bio-mechanics, we put our body in the wrong position to maximize leverage and power. Remember, swing smarter NOT harder.

In the vintage days of baseball, hitters used heavier bats made of hickory, which is a very dense and heavy wood. Names like Lou Gehrig, Josh Gibson, Babe Ruth, and Mickey Mantle used to power the ball over 550 feet without breaking a sweat...nowadays, even with the help of steroids, players have a hard time getting it to 550 foot marker, because the light weight Norther Ash and Maple bats they use.

I've heard in the televised All Star Home Run Derby, players are being counseled to sling heavier bats than ordinarily used during the season because of the physics influence.

The bottom line?

We can adopt the physics of hitting a baseball principals, but don't forget, fusing them with these 4 Swing Smarter hitting mantras...

  1. Economy of motion with NO wasted movement (swinging Down & Through),
  2. Practicing a less is more swing tempo,
  3. Hitting to all fields, and
  4. Manipulating the proper weighted bat...

Will lead to maximizing personal performance at the plate, not only physics says so, but so does math, philosophy, and science. For an informative brief article interview with Robert Adair by PopularMechanics.com on his latest baseball book, Why a Curveball Curves, check out the following article: 9 Questions for Baseball Pysicist Robert Adair

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