1 STEM NEwS: Game On!

THE PHYSICS OF PITCHING he pitcher steps up to the mound. The crowd is suddenly quiet. The pitcher is concentrating. An understanding of the science of physics will increase the pitcher’s chances of throwing a strike.

The physics concepts of force, energy, friction and drag are a big part of the game of baseball!

is always pulling a baseball (and stuff like spilled popcornat a ball game) down to the ground.

is a force that slows a moving object.

is an upward motion created by the aerodynamic force of an object through the air. This upward motion counters the pull of gravity.

THIS KIND OF DRAG IS CALLED

"WIND RESISTANCE.” BUT I CAN’T

RESIST IT!

Imagine you are a big league pitcher. Stand up and pretend to throw a baseball as hard as you

can. How far do you think it would go?

Now go outside and try it for real. Measure how far

you threw the ball.

Would it reach home plate? The distance between a pitcher’s

mound and home plate is 60 feet, 6 inches.

A ball needs a lot of energy to get overcome the force of gravity and get from the pitcher’s mound to home plate. It can’t get there by itself. The pitcher will use a wind up to throw, or put a force on the ball to give it the energy it needs to travel all the way to home plate.

2 STEM NEwS: Game On!

FAST FACTOID: The fastest pitch on record was thrown by Aroldis Chapman in 2010. The ball was

clocked at a stunning 105.1 mph (169.1 km.h). The catcher’s hand is probably still a little sore.

Does a curve ball actually curve?For a long time people thought curve balls were an illusion. But, thanks to technology and a better understanding of physics, we now know that the ball

actually does curve – as much as 18 inches by a skilled pitcher.

A curve ball is very di�cult to hit. A good pitcher can

make the baseball curve to the left or to the right or suddenly downward, leaving a frustrated batter swinging at nothing but air. Steeeee-rrrrrike!

As the ball spins, its bottom surface moves in

the same direction in which the air moves.

Topspin makes the top of the baseball spin in the

opposite direction to the air moving over the ball’s surface,

creating wind resistance.

This creates higher air pressure which pushes

against the ball, making it �y in a curved �ight path.

air pressure

Pitchers can throw several di�erent kinds of pitches to confuse the batter.

This pitch makes the ball curve away from the batter.

air �ow

wind resistance

Which pitch is which?

CUTTER

This ball drops suddenly just before it reaches home plate.

SPLITTER

This ball curves down and away from the batter.

SCREWBALL

Ball thrown with topspin

THE WIND-UP A pitcher gets a larger force on the ball with a wind-up. The wind-up uses the largest parts of the body �rst to really put lots of force on the ball.

Now, gaining momentum, he

strides forward and power moves

through his body to his throwing arm, which

rises to shoulder height behind him.

As he raises one leg bending at

the knee, he lowers his

throwing arm below his hips.

He rotates forward and with the energy generated by the movement, whips

his arm forward as he releases the ball. The force of the action leaves him

standing on one leg.

From a standing position, with the ball held high, the

pitcher coils to start the chain

reaction. Now, gaining momentum, he

strides forward and power moves

through his body to his throwing arm, which

rises to shoulder height behind him.

As he raises one leg bending at

the knee, he lowers his

throwing arm below his hips.

He rotates forward and with the energy generated by the movement, whips

his arm forward as he releases the ball. The force of the action leaves him

standing on one leg.

From a standing position, with the ball held high, the

pitcher coils to start the chain

reaction.

3 STEM NEwS: Game On!

he center �elder can scoop up a ball hit deep into center �eldand throw it more than 200 feet to get arunner out at second base.

Throwing that far is no accident — it’s math and physics!

The force of the throw gives a ball forward motion. But as the ball travels, gravity pulls it downward.(Gravity is such a downer!)

So, the ball must be thrown upwards and outwards at an angle so that it can travel the farthest before gravity pulls it to the ground.

This number gives you an idea of how well a batter hits. To �gure out a person’s batting average, divide the number of hits by the number of “at bats.”

This math formula is used to �nd out how many runs a pitcher allows in nine innings of pitching. Pitchers want to keep this number as low as possible.

Josh hits the ball half of the time he is at bat, so he has a .500 batting average.

That fraction can be reduced to

Josh hit the ball 3 times in 6 at bats. Sean allowed 7 runs in 34 innings pitched.

You can write it as a fraction:

Let’s Talk Stats Baseball fans use a lot of math when talking about their favorite players. Here’s the scoop on how to calculate these key player statistics. Learn this and you’ll sound like a big leaguer!

I hope everyone understands the

gravity of this situation!

BATTING AVER AGE EARNED RUN AVER AGE (ER A)

which is also

Sean has an ERA of 1.85, which means he allows under 2 runs every 9 innings.

Divide that number by the number of innings pitched:

To calculate his ERA, multiply the number of earned runs X 9

ANGLED FOR DISTANCE

4 STEM NEwS: Game On!

AerodynamicsExplore lift, drag and gravity by placing balls in di�erent areas of an air current at the Chevron STEM Zone Aerodynamics exhibit.

MATERIALS:• wooden baseball bat• hammer• masking tape

WHAT IS A SWEET SPOT?Baseball players try to hit a baseball on the

sweet spot of the bat, because hitting the ball on that spot makes the ball go really far!

To find the sweet spot on your baseball bat, hold the bat loosely between your thumb and fingers so that it

is hanging down toward the ground.

Have a friend GENTLY tap the bat

with a hammer every inch or so starting

from the middle of the bat and working their

way down.

As your friend taps on the bat, you will feel

vibrations traveling up the bat to your fingers.But when the hammer finds the sweet spot,

you won’t feel vibrations.

Does the hammer make a different sound

when it taps on the sweet spot of the bat? Mark the sweet spot with a small piece of

masking tape.

When you hit the bat with the hammer, it pushes the bat sideways a little, and makes the bat bend. The bend is so small that you can’t see it. But it bends and unbends really

fast – so fast that you can feel it all the way up to your hand.

If you hit a bat at the sweet spot, the bat doesn't bend as much, so you

don't feel any vibrations in your hand. Because energy is not wasted on the vibrations, more energy transfers to the ball, making it go faster and farther.

Ready for the science scoop?

Gravity is always pulling a baseball sideways (F)

Wind resistance is a drag.

A curve ball doesn’t really curve.

A splitter is a kind of a pitch.

To go further, a ball must be thrown upwards and outwards.

A batting average tells you how many bats a player owns.

Baseball players try not to hit a baseball on the sweet spot.

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