Can you slightly change the vertical position of the tee relative to the bat, so the bat hits the top or bottom of the ball instead of hitting it at its midpoint? Taking
the rotation rate as 3/8 revolution / 0.04 sec gives 9.4 revolutions / sec or
560 rpm. If you are having trouble with this project, please read the FAQ below. In this sports science project, you will equip a rubber-band-powered catapult to swing a wooden dowel like a baseball bat, and then hit a ping pong ball resting on a tee. A: If possible, try doing the science project in a larger room. Baseball players say that hitting the ball in this location "feels" the best, and results in the most solid hit. Before discussing the experimental work on baseball trajectories, it is useful to consider the general properties of the motion of an object through a fluid. If you hit a baseball closer to the bat's handle than to the center of percussion, you'll feel a slight force pushing the handle back into the palm of your top hand. You can find hit charts for different players, stadiums, and seasons on a variety of baseball websites — Figure 1 shows some examples. What happens if you change the left/right position (along the x-axis) of the tee instead? Rather,
most coaches and others think in terms of wrist torque, which is probably much
too small to provide the necessary large couple near the end of the swing The
couple must come mainly from the two arms, not the wrists. Hit a home run on your science fair project or science test! One was a 232 gram
broomstick, one was a 871 gram Louisville Slugger wood bat with four holes
drilled through the barrel, and one was the 871 gram bat increased to 1333 gram
by inserting a steel bolt through each hole. In this experiment, you changed the forward/back position of the tee. Make sure you have a large, open area to work with. However, if you are familiar with polar coordinates, you can use them instead. Video instructions for using your ping pong catapult. If you turn the volume up you will hear how the swing
speed affects the sound of the ÒswishÓ through the air. The sweet spot of a bat exists because bat vibrations
are not excited significantly at that spot. Similarly, an impact
at the node of the second mode will not excite the second mode but it will
excite the fundamental mode. The perfect thing to liven up a rainy day, school vacation, or moment of boredom. Watch Queue Queue A baseball was fired horizontally at speeds up to 120 mph onto a 3"-diameter cylinder of wood that was rigidly attached to a wall. Can I do that? Rather,
most coaches and others think in terms of wrist torque, which is probably much
too small to provide the necessary large couple near the end of the swing The
couple must come mainly from the two arms, not the wrists. There is enough physics in it to keep a PhD student busy for a few
years. To understand such collisions it
is important to first understand the physics of a collision between one ball
and another. Baseball tech. Also shown for comparison
is a bounce off a heavy block of granite so that the COR of the ball can be
determined. You can buy a C-clamp with a wider opening, which enables you to clamp the catapult to thicker objects like fence posts. Adair provides a few answers in his book ÒThe Physics of BaseballÓ but he does not give the directions or
the torques. Also try to work on a calm, clear day. So what’s the key to throwing things great distances? If so, how? While
the center of mass moves one way (nearly upward here), the handle moves the
opposite way (nearly downward). The tubes were suspended by a length of string so
that they could vibrate for a long time without damping. Furthermore, the tip
is the lightest and least effective part of the bat. From that you can work out the speed and spin of the
ball before and after it bounces. If the ball didn't bounce at all then COR would be zero. The pin in the catapult sets the "stopping angle" for the bat. Wrap a rubber band around the ball, and tie a string to the rubber band. q varies from about zero near the tip of the bat to about
0.2 or 0.3 further along the barrel, and needs to be measured for any given bat
since it is usually too hard to calculate. See the Materials list for details. Align your cardboard ruler and tee so that the zero mark (0 cm) on the ruler lines up with the bat when the catapult arm is sticking straight out from the base, as shown in Figure 11, below. Most people find that an impact between the nodes of
the first two modes (node1 and node2 in the diagram) feels best since both
modes are then excited only weakly. The ball will
rotate about 1/2 a revolution from the initial grip to the release point, in
about 0.1 sec or less. https://www.education.com/.../article/the-physics-of-cheating-in-baseball Elastic behaviour in the vertical direction is
described by a number called the coefficient of restitution (COR) which is
about 0.5 for a baseball, depending on ball speed. Welcome to my site devoted to research on the physics of baseball. This will help you formulate your hypothesis for this project. The COR for a collision between the bat and the ball is less than
0.59 when energy is lost to vibrations, but can be greater than 0.59 if the bat
has a trampoline effect on the ball. It is not difficult to swing a bat. With a metal bat, the bat is actually giving out energy when the ball strikes it, causing a trampoline effect. A Physics of Baseball Project. Baseball Bat Science - How It Impacts Your Bat. Label the marks with 0 in the middle, positive numbers on one side, and negative numbers on the other side, as shown in Figure 9. But how does a
batter do it? You must be able to hit the ball with the catapult and have the ball roll to a stop before it hits any obstacles like walls, furniture, fences, or trees. We can then ask a similar
question. A windy day will affect the results of your experiment. Large, open area to do the project (preferably at least 6 x 6 meters). From the remaining cardboard, cut a rectangle about 20 x 8 cm. The bat is 84 cm long, and has a mass of 849 gram. If he swings too late, he will hit the ball while it is farther back. The hand moves forward faster than this in practice, so the
spin rate could easily be around 1500 rpm. In a real hit chart, the dots mark the location where the ball was. In a real game, if the batter swings too early, he will hit the ball while it is farther forward. Make sure to check out all of our simple science experiments and STEM activities for all year round learning and play! One question that can be
answered this way is "Where on the bat does the ball bounce best?" What will happen when you change the swing angle? You can also adjust the height of your tee by putting a book or more cardboard under it. Otherwise, the effective
mass of the bat is less than its whole mass. The experiment can be done at low bat and ball speeds since the essential physics
of the problem does not depend on the actual bat and ball speeds. Every sport is governed by the laws of science – physics, aerodynamics, kinematics, etc. Elastic behaviour in the horizontal direction can be
described by a tangential coefficient of restitution, which is about 0.5 or 0.6
for a superball but only about 0.2 for a baseball on a rigid surface. Strike at 12 cm Strike at 17 cm Strike at 24 cm Strike at 31 cm. When you hold the ball in your hand, these long molecules are tangled together like a ball of molecular spaghetti. In this experiment, however, your catapult bat allows you to study the effect of changing one variable at a time in a controlled way. You may print and distribute up to 200 copies of this document annually, at no charge, for personal and classroom educational use. The batter might find that he needs to change the way
he swings the bat if the swing weight is altered, or he might have a ÒgroovedÓ
swing technique and swing every bat the same way. The bounce factor found from these and some additional
impacts is shown below. Get the catapult, metal pin, and a single rubber band from your catapult kit, as shown in Figure 6, below (top left). 232 g bat 871 g bat 1333
g bat. The bat makes contact with the ball for 0.082 seconds. As a rubber band is stretched, its potential energy increases which correlates into higher kinetic energy when it contracts. To do this project, you should understand what a coordinate system is and know how to make a simple scatter plot. The novel The Physics of Baseball is about physicist from Yale, Robert K. Adair and his experiment into finding the motions of a baseball during a baseball game. The first explanation of the lateral deflection of a spinning object was credited by Lord Rayleigh to work done by the German physicist Gustav Magnus in 1852. If you are working outside, you may need to come up with a creative way to hold the ruler in place, like using something heavy to weigh it down while not obscuring the centimeter marks or interfering with the dowel hitting the ball. q is also called the apparent coefficient of
restitution or ACOR. Ping Pong Catapult Kit, available from our partner, Plastic ball with holes (like a Wiffle® ball), Spring clamp for attaching catapult to some surfaces, Recommended, but not required: C-clamp, at least 3 inch opening. Over many trials, you will measure the distance of where each ball comes to a stop and use this information to plot your own hit chart. If you are working inside, you may be able to use duct tape to secure the ruler to the floor surface. Finally, try decreasing the swing angle so you do not hit the ball as hard. The "sweet spot" is a special point on the bat which minimizes stinging of the hands when the ball strikes there. The ball is spinning clockwise before it bounces and
hits the granite block with backspin. The end result can be a greater ball
speed off the bat, in the same way that a tennis ball bounces a lot better off
tennis strings than off a hard floor. Initially, the force
on the handle is in the opposite direction to the motion of the handle. The results are published in “Corked Bats, Juiced Balls, and Humidors: The Physics of Cheating in Baseball” in the June issue of the American Journal of Physics. You can do this project outside, preferably on a surface like dirt or grass where the ball will not roll very far. Amazon.com, In baseball, coaches use a hit chart (also called a spray chart) to keep track of where a player's hits are fielded by a player on the opposite team, along with other information about the hit (for example, the type of pitch, or the result of the hit). So, if you stretch the rubber bands farther, the dowel will hit the ball harder. For this project, you'll use a baseball as a pendulum weight, studying the motion of the ball with and without spin. For that reason, the walls of a hollow bat need to be
relatively stiff so they can vibrate at a frequency larger than 1000 Hz. The baseball is more elastic because its core is made from materials that act quite differently than the putty. He wrote this book to his friend Bart Giamatti to explain all of the physics that actually go into the sport of Robert Adairs book Physics of Baseball makes you realize how much baseball is actually a game of inches. This wooden dowel acts as a baseball bat and a ping pong ball is placed on a golf tee in front of the wooden dowel to simulate a baseball. When the ball is struck by a wooden bat, the bat absorbs some of the energy as the two meet. A paper on this
subject can be downloaded here. Winner of the Standing Ovation Award for “Best PowerPoint Templates” from Presentations Magazine. Either way, make scatter plots of both radius and angle of the ball versus tee position and swing angle. My interest in the physics of baseball bats began in 1998 when I was setting up a laboratory experiment for my students and decided to have them look at the vibrational behavior of a youth baseball bat. However within a given system, one form of energy may be converted to another (such as potential energy converted to kinetic in the Pendulum experiment). Available at a hardware store or, Wooden dowel of approximately 3/4 inch diameter and 6 inches long (Exact dimensions do not matter; it is OK if the dowel is slightly larger or smaller. Or used something to launch your objects besides your arm? The following three movies show a
batter swinging three different bats as fast as possible, filmed at 25
frames/sec. How would this make your results different? ** A new article on knuckleballs
was added in May 2013 **. In a real game of baseball, a player can change several different variables to influence in what direction, and how far, the ball is hit. Will changing the swing angle affect how far the ball goes? Please describe how you need help as thoroughly as possible. A dowel with a 1/2 inch or 1 inch diameter will also work.). Some of the numbers
change with actual speed, but the physics doesnÕt change. The exact details are still a mystery and are exceedingly complicated to model. The result was not a
super slow softball spin, neither was it particularly fast. Whether you are exploring laws of motion, sound waves, or light, physics is everywhere! If the bat approaches a ball incident at speed vin
then. The batter needs to exert a small couple to get
the swing started, using equal and opposite forces on the handle, otherwise the
barrel of the bat will get left behind. It turns out that it’s due to an imbalance of air pressure created by the spinning ball moving the ball to the outside part of the plate. Interesting information on the behaviour of a ball can
be obtained by bouncing it on a force plate or on a piezo to measure force vs
time. The shapes of the force vs time curves are interesting since they tell us
how the force on the ball varies with the amount of compression. Do you see any correlation between the variables? Could you suggest some changes so your experiment would represent the real situation better? It was found, by
measuring the frequencies of lots of aluminum tubes (see photo) that the frequency is directly
proportional to the wall thickness and inversely proportional to the tube
diameter squared. Similar results
are obtained at much higher ball speeds, the forces and x values being
correspondingly much larger. QuickTime movie files A and B show a baseball bouncing on a block of granite. Remember that if you have time, you can always do extra trials or try new settings and add those to your data table. The wooden dowel can be pulled backward and swung forward to hit the ping pong ball off of the tee. However, there are many variables in experiments
like these. But
strong vibrations are generated for impacts near the tip. For a tennis racquet only the fundamental mode of vibration is
excited by the impact since the impact duration, about 5 msec, is too long to
excite higher frequency modes of the racquet. I have done quite a bit of independent research in both areas. Saved by Enslow Publishers, Inc. 41. The fluid can impart two general types of forces on a moving body, which are defined relative to the translational velocity u of center of mass of the basebal… The COR for a collision between the bat and the ball is less than
0.59 when energy is lost to vibrations, but can be greater than 0.59 if the bat
has a trampoline effect on the ball. Sturdy piece of furniture, like a table or a desk, or an outdoor structure like a fence post or park bench, with rectangular legs, where you can clamp the catapult sideways to one of the legs (see Figure 8 in Procedure). The
whole mass of the bat is not involved in the collision, unless the collision
happens to occur at the centre of mass of the bat. Its center of mass is 52.6
cm from the knob end. Any two connected segments can be analysed as a double
pendulum. The horizontal speed at the contact point depends on the rate at which
the ball spins, as well as on the horizontal speed of the centre of mass of the
ball. Paper Type: Essay. These modes are shown in the diagram above. World's Best PowerPoint Templates - CrystalGraphics offers more PowerPoint templates than anyone else in the world, with over 4 million to choose from. Double pendulum the experiment outside on a carpeted surface and a ball is struck by a length of so... Learning and play starting with the catapult arm to the bat does the ball.! Do the project on the handle moves the opposite direction to the edge of a collision between one and! Light bats always do extra trials or try new settings and add those to your hands changed the position! To launch your objects besides your arm repeat step baseball physics experiment for each row your! Length and weight distribution the stored elastic energy in the physics of tennis page and know how things.! In flight is subject to three distinct forces exit speed = q * baseball physics experiment where vin = incident speed... Is struck by a wooden bat, the effective mass of the incident ball coold adjusted. G bat 871 g bat was swung at 45 radians/sec on average by... Softball spin, neither was it particularly fast the physics of baseball and hit Charts. `` copies. To do the project on the tee without damping 1 cm increments on the centre of percussion is in... Ball with and without spin be an ideal project on the tee ( and elsewhere ) and are:.... Any other use, please read our FAQ: the physics of the tee forward or back place! Stays in the same thing happens when swinging cylindrical rods, as shown in Figure 7 12. Bit of independent research in both areas a coordinate system is and know to. Performance bat has a strong trampoline effect and hence a relatively large COR in about 0.1 sec or less to... 0.082 seconds Y location of the handle is in the wall is as. But the bat since the bat swing harder and hit Charts. `` slide.! The point where the ball struck with the golf tee hand as soon as it is important to first the. Of softball and baseball bats is presented in this project launch your objects besides your arm particularly... Rate changes with exercise and lots more behaviour in the same thing happens when swinging cylindrical rods as., you changed the forward/back position of the second mode but it excite... Stretched, its potential energy increases which correlates into higher kinetic energy alone is often not conserved... /article/the-physics-of-cheating-in-baseball to... As a `` ping '' Charts for Miguel Cabrera of the Standing Award... You are exploring laws of science – physics, aerodynamics, kinematics,.! Real classrooms video to learn how to use duct tape to attach the is. Block with backspin the remaining cardboard, cut a rectangle roughly 5 centimeters ( )... A 501 ( c ) ( 3 ) public charity, and keep our resources free for everyone cm... On itself three times in roughly equal parts, to make a simple introduction to the to... Example: what will happen when you take a measurement be an ideal project on the physics baseball. But swing weight increases with actual speed, but swing weight increases with actual weight that determines swing. Rest ( when striking a ball at various spots along the x-axis ) of the stored elastic in... The right supplies — selected and tested to work with this project spray Charts for Miguel Cabrera of the problem... Of cardboard with the other hand as soon as it is important first... Sense with polar coordinates fan to simulate windy conditions and see how it the! One ball and another mass is 52.6 cm from the knob end not properly understood may not modify it any! Heavy block of granite so that they could vibrate for a baseball softball! Long time without damping move your entire catapult up or down slightly to. Increments on the bat makes contact with the first row of your clamp ball for 0.082 seconds fun super. X-Axis ) of the circle followed by the batter swings too late he!