HYPOTHESIS•A ball hit with a wood bat will travel farther than a ball hit with a metal bat.
Newton's second law.
Wood vs Metal • Wood• Greater Mass• Weighs more• Natural• Solid• Small sweet spot
• Metal• Hollow• Acceleration • Does Not Break• Man Made• Large Sweet spot
WOOD BAT WEIGHT AND MASS
Is a wood bat stronger? Yes or No
Mass- is a measure of total quantity of matter in an object (Mass of a bat is a constant) Weight- Weight is a measurement of the gravitational force acting on an object (Weight of an object varies with the object’s geographical location)
Example: A 19oz bat at Woodward Academy weighs less at the equator and on the moon but the mass stays the same.
Is a Wood bat Solid?
YES• Solid Is the physical state of a shape
and a volume.
The three states of matter are – Solid: Wood is packed closely together – Liquid: Units are not packed closely together – Gas: Vapors are far apart.
Wood Batsare made of Natural Material
• Wood is a pure substance that cannot be changed to other kinds of matter or physical means.
• Wood is a common substance used in everyday life.
– Home building – Heating homes– Making Furniture– Making Tooth picks – Making Baseball bats– Making Pencils And Paper
Wood Bat SWEET SPOT
What is a sweet spot? A perfect small area on the barrel of the bat. The Preferred area of the bat to hit the ball.
What happens when you hit the ball on the sweet spot?
The ball travels farther because of Newton's 2nd law of motion (F =M x A)
What happens if you don’t hit the ball on the sweet spot?
Bat vibrates and takes away energy from the ball.
If the ball is not hit on the sweet spot the ball does not travel as far.
Metal Bats are HollowHollow means having a closed body which is not filled (bat barrels are empty)
weight is distributed different than a wood bat.– Center of mass for metal bat is closer to the handle.– Center of mass for wood bat is closer to the barrel.
Balance point: point on the bat where the weight can be balanced on both sides.– Lever first class : fulcrum is in the middle and the load and effort is on
either side– Think of a see-saw
Inertia of the bat makes all the difference – Inertia is Newton's first law of motion: an object at rest stays at rest
and an object in motion stays in motion.
What does this mean?: center of mass is influenced by balance point which affects inertia.
Metal bats are 5-7mph faster than the wood bat
Aluminum bats have the Trampoline effect– When a wood bat hits a ball it compress and loses
75% of it’s energy.– When an aluminum bat hits a ball it compresses
but loses a fraction of it’s energy.
– What makes this possible?– Energy -Comes from the batter’s body into the bat to the ball– Inertia -Comes from the bat moving to the ball.
METAL BATSDON’T BRAKE
• Metal is strong– The handle is a thin metal tube with thick
– The barrel is made of thin metal which may dent or crack but will not break.
– Wood bats are made with wood or ash and will break if the bat hits the ball towards the middle closer to center of mass.
METAL BATS ARE MAN MADE
How are metal bats made?– Sprinting Toward First Base
– Ironing process metal heated up to 900 degrees to create the barrel and the handle.
– Passing Second Base – Cleaning, Heat Treating, and Aging– Heating treatment and aging up to 300 degrees
– Rounding Third Base– Capping, and Silk Screening – Polishing
– Safe at Home Plate - Final Assembly and Packaging) -Rubber grip and chemical coating.
THE WOOD BAT IS STONGER AND HAS MORE MASS
BUT THE HITTER CAN CONTROL THE METAL BAT BETTER..
METAL BAT LARGE SWEET SPOT
Is a metal bat’s sweet spot larger than a wood bat’s sweet spot?– Yes because of the contact surface.
– Metal bat has a large contact surface» Resulting in more hard hit balls» More home-runs with a good swing not a perfect swing
– Wood bat has a small contact surface» Resulting in ground out or fly out» Home-runs must be a perfect swing.
– The wood bat center of mass is close to the end of the barrel.
– The center of mass of the metal bat is closer to the handle.