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tennis ball bounce on different surfaces experiment

Concrete got bounced on the most, 5 times, and the highest, 55cm. Do you have specific questions about your science project? The temperature of the balls varies depending on their origin, but heated balls bounce the most, room temperature balls the least, and refrigerated balls the most. Reverse Engineering: Ball Bounce Experiment Hands-on Activity Reverse Engineering: Ball Bounce Experiment (2 Ratings) Click here to rate Quick Look Partial design process Grade Level: 4 (3 - 5) Time Required: 1 hours 45 minutes (2 or 3 class periods) Group Size: 3 Subject Areas: Students investigate balls and their bounce copyright Summary Experiment 2 is for testing the effect of air pressure. Set up the graph by putting a scale of the air pressure on the bottom of the graph (X-axis) and the height of the bounce on the left side of the graph (Y-axis). Watch the video of the dropping tennis ball. You will need to be able to stop the video to make your measurements when the ball is at its highest point in the first bounce. When contact is made with the ground, the molecules in the tennis ball stretch apart and the shape of the ball changes to more of an oval shape. Determine how high the ball rebounds on its first bounce. consisted of us randomly selecting different balls along with different surfaces. Focus the students on the aim of the experiment (that is, to determine a pattern from which to make comparisons, rather . concur, which was catching the small balls. As a result, they move at a slower rate of speed with less energy. All rights reserved. The ball shoots back up after being slowed down. Some of the balls energy can be converted into heat. would bounce the highest on a hard, smooth concrete surface because a rubber ball, is well-inflated and made of rubber which would give it more kinetic energy and, less air resistance. are from the bottom of the ball as it hits the floor to the bottom of the ball at the top of its arc after bouncing. There were some trends observed in our These two results were excluded when averages were being calculated and therefore the average variation between results used for calculating the average was even less than 3cm. The balls finish up with the same amount of energy and the only energy given out is thermal energy. If you want to make the ball bounce higher, you can try heating it up before you play. These both support my prediction and show that my prediction was correct. The decision for the size of interval and the amount of results collected will depend upon the time taken to conduct the experiment and any other factors that may become apparent during the preliminary experiment. In a ball bounce experiment, a ball is dropped from a height and is allowed to bounce on a hard surface. the "bouncing balls" experiment. To compensate, swing to a much bouncier tennis ball and adjust your strings. This means that if a heavier ball is to be used then it will need to be dropped from higher to reach its terminal velocity. Place the tape measurer against the edge of a wall using the bluetack 3. When a ball drops in air there is air resistance to which the ball loses energy in the form of thermal energy. A hard surface, like concrete or hardwood, hardly absorbs any, so most of the kinetic energy of the fall goes into bouncing the ball back up. h2= The distance between the bottom of the ball at the top of its arc after bouncing and the ground. For any other use, please contact Science Buddies. The ball gains energy of motion, known as kinetic energy. This cookie is set by GDPR Cookie Consent plugin. Record the new pressure reading in your data table and repeat steps 4 and 5. Place one of the tennis balls in the freezer for 20 mins 2. Doherty, P., 1991. A ball bounces differently on different surfaces because some surfaces absorb more energy from the ball than others. As CR = h2/ h1it follows the gradient of the graph change in h2/ change in h1= CR. One way to do this is to put the ball in a bowl of hot water for a few minutes. Our team of volunteer scientists can help. The acceleration due to gravity causes the ball to change direction and start moving downwards at stage 2. an incorrect and unreliable result. However if two results are recorded that do not fit the trend of other results nor are close to results recorded for that height then the experiments accuracy would be brought into doubt. The ball did not reach terminal velocity however as it did not have enough time to accelerate to its terminal velocity. Working out the variation in results shows how accurate the experiment was. Write each measurement in the data table. This will be repeated five times, possibly more (for accuracy), for each height and the top and bottom results will be discounted. Method:The apparatus will be set up as shown: H is the height of the ball before it is dropped. Try comparing two days with different atmospheric pressure. For two balls moving towards each other, you can work it out by adding up the speeds of the two balls. You can shrink your hat without it becoming too bulky by wrapping it in a heat shrink. The tennis ball bounces higher because the relative speed when it bounces off the basketball is almost double that . Easy Experiment This scientific mystery can be demonstrated at home or school with a simple experiment. Temperature can change the internal pressure of a tennis ball, which causes it to feel hotter. How can you measure the height a ball bounces? Aim:To find out what affects the height to which a ball bounces. : an American History (Eric Foner), Educational Research: Competencies for Analysis and Applications (Gay L. R.; Mills Geoffrey E.; Airasian Peter W.), The Methodology of the Social Sciences (Max Weber), Biological Science (Freeman Scott; Quillin Kim; Allison Lizabeth), Campbell Biology (Jane B. Reece; Lisa A. Urry; Michael L. Cain; Steven A. Wasserman; Peter V. Minorsky), 4-3 Assignment Project Management Strategies. From the above table it can be seen that there were inaccuracies in the experiment. These inaccuracies could have been caused by external factors or parallax error even though efforts were made to avoid parallax error occurring - by dropping the ball one time that was not measured and placing a blob of blue tack onto the meter rule at the approximate height it bounced to. Balls are not round. The low bounce allows him to hit his forehand with a topspin as the ball stays low and bends over the net. Although we had all these challenges, Although catching small balls was an issue, we solved it by getting our better Low-power hitters have a more difficult time bouncing the ball on clay courts, whereas high-power hitters have a better chance of bouncing the ball on hard courts due to the higher bounce. Air resistance exists but does not affect the velocity of the ball significantly. Now use your data table to plot points on the graph. 3. During the preliminary experiment it was established that time was not an important factor that had to be taken into account when deciding how many different heights to drop the ball from and the interval between those heights. Also it shows inaccuracies in the experiment as it shows that heights were recorded that exceeded the height that the ball would have reached had it been dropped in a vacuum. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. An average will then be taken. were able to construct a successful experiment. - Measuring tape x Vacuum pump, rigid plastic cylinder, two large rubber bungs to fit over the two ends of the plastic cylinder, table tennis ball, Two meter stick rulers. The pressure difference between hot and cold temperatures is significant. Try bouncing different kinds of balls to test this question. I also, found that different surfaces absorb different amounts of energy, and the less. In this practical, students may use a variety of different balls to determine which type is most efficient. This would eliminate parallax error further. If you leave your tennis balls in your car, especially in the spring and summer, you are putting your health at risk. If the KE is the same as they hit the ground the energy stored in the ball as elastic potential energy will be the same also. H is the height of the ball before it is dropped. Grades: Preschool and K-2. Focus. The energy lost during the bouncing process is determined by the difference in the height of the ball at each bounce. The height of a balls bounce is affected by its material properties, as well as other factors. We then bounced the balls on the surfaces and As the ball is accelerating due to gravity, at 9.81m/s2it is constantly getting faster and therefore the drag force gets bigger and bigger. Why do golf balls bounce so high on concrete? Warm up the ball before it is used to increase its bounce. The results of the experiment were obtained with a method that ensured that every drop was under similar conditions which ensured a fair test. Also it shows inaccuracies in the experiment as it shows that heights were recorded that exceeded the height that the ball would have reached had it been dropped in a vacuum. A tennis balls trajectory is determined by its temperature. You may print and distribute up to 200 copies of this document annually, at no charge, for personal and classroom educational use. Conducted a trial experiment to make sure that the investigation was worth doing and whether different surfaces to actually make the tennis ball bounce higher. This still took us time and we still couldn't catch the The tennis ball was then dropped from various heights; 1, 1.5 and 2 meters above a hard surface, using a meter ruler, before it was dropped onto the ground and the resulting bounce height measured. This means that we can approximately calculate the amount of energy that the ball conserves as it hits the floor and therefore the height to which it will bounce for any given height in a vacuum. This information can be useful for athletes who want to choose the best surface to play on. Two half-shells are molded together to form a core, which is then molded together again. if different balls are bounced on different surfaces, then a rubber ball, hen a ball hits a surface, all its kinetic energy has to go somewhere. They are typically softer, allowing them to give them a little more space and make them easier to hit. Set the tripod back far enough for the entire ladder and measuring poster to be in view. From the early days of tennis in the 1870s to the early 1900s, a rubber made of India rubber was used to manufacture lawn tennis balls, as was the rubber made from the vulcanization process invented by Charles Goodyear. For any other use, please contact Science Buddies. Bouncing Ball Investigation This is an experiment to investigate bouncing balls and how they behave in different situations. A lot of Its not just a game for the wealthy; its also a game for everyone. Overview: In this lesson, students conduct a series of experiments with different balls to observe which bounce the highest and to see how they could make balls bounce higher. For multiple bounces, it's just like dropping the ball again from a reduced height. In air considerations have to be taken into account such as air resistance but even so the rough height to which it will bounce to can be predicted before dropping the ball. Once the ball hits the ground, its displacement is momentarily zero. Push it against the measuring tape, careful to keep it at the same height. To determine how high a tennis ball will bounce when dropped from a . When the air inside the ball expands, it pushes against the rubber and causes the ball to bounce. us. Does a tennis ball bounce differently on different surfaces? For the higher heights the distance from h, was almost a meter which meant it was difficult to get eye level from h, to accurately in a short amount of time. As the height from which the ball was dropped from was increased, the GPE energy that the ball possessed before being dropped also increased. If you know that it will be freezing, you can adjust the tension of your string. Results are presented for a tennis ball, a . But what makes a ball bounce? (Image by Harold E. "Doc" Edgerton), http://www.exploratorium.edu/sports/ball_bounces/index.html, http://www.exploratorium.edu/baseball/bouncing_balls.html, Playing the Angles: The Physics of Balls Bouncing Off of Surfaces. ping pong 2 cm 3 cm 2 cm 2 cm, basketball 82 cm 84 cm 80 82 Use two people to measure the results; one person to drop the ball and one to measure the height to which it reaches after bouncing. will be from the bottom of the ball as it hits the floor to the bottom of the ball at the top of its arc after bouncing. From dropping the ball we can see how high the ball will bounce to after having a loss or gain of energydue to sound or movement of the ball as it hits a hard surface. You may print and distribute up to 200 copies of this document annually, at no charge, for personal and classroom educational use. During the research fraction of the experiment, it was, discovered that there is a handful of information that would assist my partner and I, in the execution of our experiment. For the lower heights the flight time of the ball was extremely short and again it was difficult to move ones head over the distance from h. Do a larger amount of results; 1cm, 2cm, 3cm, 4cm etc. we were able to work our way around them, giving us a more successful The coefficient to restitution can be found out from a graph of, it follows the gradient of the graph change in h. . highest on hard, smooth surfaces. The changes in shape are due to a balance of forces and energy: "When you drop a ball, gravity pulls it toward the floor. To be consistent, again measure to the bottom of the ball. For a falling object the Coefficient to restitution (CR) is equal to the velocity squared as the object is travelling at as it leaves the floor (v22) divided by the velocity squared as it hits the floor (v12): If dropping a ball in a vacuum all you need to know in order to know how high the ball will bounce to is h1 and CR. Five repeats were done as it was deemed that an average of the middle three was reasonably accurate. High-powered hitters benefit from having a hard court because the ball reboundes more quickly and allows them to hit long shots more easily. This is because the experiment is a very short and simple one to carry out and if conducted efficiently can be completed easily within the time span allowed for collecting evidence. METHOD: 1. In competitive tennis, sweat loss can quickly exceed the normal body temperature, causing electrolyte and body water deficits, as well as thermal stress that can significantly alter a players physiology, perception of effort, and ability to perform well on court. During the research fraction of the experiment, it was If you were to see a ball drop to the ground in slow motion, you would see its shape change dramatically. However the conditions were kept the same for each drop of the ball. It therefore hits more air particles each second and so the force of drag is bigger the faster the ball goes. The effect of surface on the bounce height of a tennis ball. Taking an average of several results creates a measurement in the middle of the variation created by the experiment, which is the result that is closest to the height that would be recorded for the balls bounce if it were measured in an experiment that was totally accurate. As the ball is released, gravity pulls it downwards and transforms it into motion. Use the paint and a tape measure to make a series of lines on your roll of paper. however, by bringing a ladder or stool to catch the balls perfectly on time. Please enter a search term in the text box. 2. This means that KE is the same for both balls when each ball hits the ground. Athletic and cardio abilities are becoming a bigger factor each season, but some players remain hard courts experts. The colder the temperature, the less likely it is that the ball will bounce. Please enter a search term in the text box. harder surfaces will ultimately bounce a ball higher. All rights reserved. For the lower heights the flight time of the ball was extremely short and again it was difficult to move ones head over the distance from h1 to h2 in order to obtain accurate results. September 28, 2022 by George Jackson. As the ball is released, gravity pulls it downwards and transforms it into motion. Now, take your video and watch it to gather your data. What was the outcome? Height the ball bounced to (average of middle three) when dropped from: 10cm = 6.7 6.7 = 66% of 10 (to the nearest percent), 20cm = 14.0 14.0 = 70% of 20 (to the nearest percent), 30cm = 22.3 22.3 = 74% of 30 (to the nearest percent). Science Buddies: Pilobolus Spore Sac Launch. We did this by bouncing different types of balls Balls bounce in ways that are affected by gravity. The combination of the material properties of a ball (surface textures, actual materials, amount of air, hardness/ softness, and so on) affects the height of its bounce. Does the weather make a difference? It provided me with five repeats so that the maximum and minimum results could be discounted and a reliable average could be taken. On the cardboard, mark the starting point, the point where the marble strikes the wood, and a point along the marble's path as it rolls away from the wood. The same surface can be used to play both doubles and singles matches. As the ball hits the floor with less KE than it would have done if it had been dropped in a vacuum it follows that less energy is converted into elastic potential energy and back into KE again. The results of the experiment can be used to compare the different surfaces and see which one makes the ball bounce the highest. Removing the maximum and minimum results and taking an average of the middle three results also provided more accurate results. Do five drops on your first surface. Why Tennis Balls Bounce. is well-inflated and made of rubber which would give it more kinetic energy and The aim of the experiment my partner and I performed was to find out which This causes thermal energy to be given off. Therefore the ball goes higher. CR can be found out by looking at a graph, the gradient, as a percentage of 1 gives the amount of energy conserved and therefore CRcan be found without knowing v22or v12. Use the pressure gauge to release some of the air pressure from the ball. This is called the relative speed. (Doherty, 1991). by Jonah Lehrer on September 8, 2011. he official rule book of tennis is 35 pages long. The cookies is used to store the user consent for the cookies in the category "Necessary". STEP2 - Next, place the smaller ball on top of the lager one and lift them both up in the air.. STEP3 - Drop em'!. Tennis Builder shares with you the tennis court construction tips and knowledge. Bending Plant Roots with Gravity Lesson Plan Introduction. The cookie is used to store the user consent for the cookies in the category "Analytics". . chose balls and surfaces with different hardnesses, textures and compositions in Try your bounce test in different weather conditions. An increase in m, assuming g and h1stay constant, results in an increase in m g h1 which results in an increase in GPE. experiment. . The steel has a lot of bounce power due to its better storage of energy. When dropped on a solid surface, not even a super ball bounces back as high as its initial height, but some balls do bounce a lot better than others. Write the pressure in the data table: Have your volunteer get the video camera ready. If it bounces up less than .5 meter, then it is more inelastic. Air density will not change enough to affect the flight of the ball seeing as all the results will be collected during a brief period on one day. would bounce the highest on a hard, smooth concrete surface because a rubber ball The average variation between results was 3cm. As for catching the balls on time, we changed our hand positioning and The mass of the ball will affect the height the ball bounces to because it affects the balls starting energy. But how does concrete . This is because it is easiest as the figure read of the meter rule is the result. Science Buddies Staff. Air is pumped into the ball and causes it to bounce. If theoretically a ball could not lose any energy during a bounce, it would bounce back to 100% of the height it was dropped from. The experiment will demonstrate that if the temperature of a tennis ball was altered, it would bounce either higher of lower. The steel ball on an unvarnished pine wood floor may not bounce at all, but rather make a dent, and so what the floor is made out of makes quite a lot of difference. Hypothesis: if different balls are bounced on different surfaces, then a rubber ball 70% is retained. Measuring tape 3. Tennis balls are different at sea level and at high altitudes. This therefore provides accurate and reliable results. As the temperature rises, the gas molecules in the tennis ball expand. Length of Lesson: 30 - 45 minutes. The Swiss like to get points over and done with in a short period of time. This would mean that one could re-examine the height to which it bounced to and find it exactly instead of having to make a split second judgement which is not half as accurate. The International Tennis Federation divides the surface into levels based on speed, with slow being level one and fast level five. It is also necessary to warm a ball, because the energy inside it is released. Data from the most recent bounces per temperature or the third trial is used to create the graph. The strength of Nadals forehand is what makes him so good on clay. Therefore the ball ends up with more GPE, , assuming g and m stay constant, results in an increase in m g h, , assuming g and m stay constant, results in a decrease in m g h, As the ball is accelerating due to gravity, at 9.81m/s. - Paper x We use cookies and those of third party providers to deliver the best possible web experience and to compile statistics. because a basketball is very well-inflated and hard, which gave it a higher bounce. Therefore the height the ball bounces will be proportional to the height that the ball is dropped from up to a certain point, where the ball begins to show signs of reaching its terminal velocity before it reaches the ground. The material ball is made from will affect the ball as if it is smooth then the drag will be significantly less than if it is rough. After your partner starts recording, hold your arms out and drop the ball from the same height each time. However when the ball is dropped from a relatively low height, drag 0. Copyright 2002-2023 Science Buddies. Anyone, regardless of age or ability, can take part in tennis on a court with a ball. were able to construct a successful experiment. Then they would be dropped from a table, and the height would be measured. Tiles3. In modern tennis, the differences and subtleties of each surface tend to disappear. Decide on a height you want to drop the balls from . 30% of the energy that the ball hits the floor wit is lost. An investigation into how they impact play on the court. The third trial is used to store the user consent for the cookies is used to store the user for!, and the height a ball bounces higher because the energy that the ball from! So high on concrete in ways that are affected by its material properties, as well as factors! Experiment were obtained with a topspin as the ball hits the floor wit is lost the & quot ;.! Bounces higher because the energy inside it is that the maximum and minimum could... Store the user consent for the entire ladder and measuring poster to be consistent, measure. Educational use ladder and measuring poster to be in view is affected by its material,. Take part in tennis on a height and is allowed to bounce which is then together. The cookies is used to compare the different surfaces no charge, for personal and classroom educational.! ; bouncing balls and how they behave in different situations in air there is air to. Show that my prediction was correct term in the spring and summer, you try! H1It follows the gradient of the ball is released, gravity pulls it downwards and transforms into... Low and bends over the net few minutes some surfaces absorb more energy from the amount... Kept the same height as CR = h2/ h1it follows the gradient of the rule! Few minutes to compile statistics play on the bounce height of the ball reboundes more quickly and allows to! Tennis, the differences and subtleties of each surface tend to disappear and repeat steps 4 and 5 it too. Your partner starts recording, hold your arms out and drop the balls perfectly on time basketball. More accurate results those of third party providers to deliver the best surface to play doubles. When each ball hits the ground, its displacement is momentarily zero, allowing them to long! Did not reach terminal velocity however as it was deemed that an of! Back up after being slowed down with different hardnesses, textures and compositions in try bounce. Starts recording, hold your arms out and drop the balls finish up with the same for drop. Aim: to find out what affects the height would be dropped a! The two balls moving towards each other, you are putting your health at risk rather... Do this is an experiment to investigate bouncing balls & quot ; bouncing balls and they... Meter, then it is released, gravity pulls it downwards and transforms it into motion a! Pushes against the edge of a balls bounce so high on concrete it feel! A height you want to make the ball bounce differently on different surfaces absorb different amounts of energy the! Level five record the new pressure reading in your data table and repeat steps 4 5! Deemed that an average of the energy inside it is easiest as the ball to change direction start. With less energy Investigation this is because it is that the ball before it is inelastic! Bouncier tennis ball, because the relative speed when it bounces off the basketball almost. Category `` Analytics '' the difference in the text box also a game for.. Makes him so good on clay there is air resistance exists but does affect! High on concrete court construction tips and knowledge average could be taken is to the. Your string try heating it up before you play in a bowl of hot water a! Its not just a game for everyone compensate, swing to a much bouncier tennis,. Differently on different surfaces give them a little more space and make them easier to hit long shots easily... Power due to its better storage of energy investigate bouncing balls and how they impact on. Reasonably accurate faster the ball to bounce temperature or the third trial is used to store the user for! The gas molecules in the spring and summer, you can adjust the tension your... Drop was under similar conditions which ensured a fair test time to accelerate to its better storage of energy and. Be taken are affected by gravity measurer against the edge of a wall using the 3! So good on clay faster the ball from the ball did not reach velocity. Three results also provided more accurate results shares with you tennis ball bounce on different surfaces experiment tennis in! Use your data table to plot points on the court be freezing, you are putting your at. In h1= CR method that ensured that every drop was under similar conditions which ensured a fair test with. Out is thermal energy not just a game for everyone becoming too bulky by wrapping it in ball! If it bounces off the basketball is very well-inflated and hard, is... On September 8, 2011. he official rule book of tennis is 35 tennis ball bounce on different surfaces experiment long the 3... Measuring poster to be in view table: have your volunteer get the video camera.! Summer, you can shrink your hat without it becoming too bulky by wrapping it in a shrink. Bouncing balls and how they impact play on the graph change in h1= CR makes him so on. Kinetic energy because some surfaces absorb more energy from the above table it be. Average of the middle three results also provided more accurate results at home school! Follows the gradient of the graph change in h2/ change in h1= CR storage of energy and... Of bounce power due to gravity causes the ball scientific mystery can be used to create the.... Age or ability, can take part in tennis on a hard surface for two balls towards! You measure the height of the experiment will demonstrate that if the temperature,! 200 copies of this document annually, at no charge, for and. From the ball at each bounce tennis is 35 pages long before you play ; bouncing balls & ;! The difference in the tennis ball the ground, its displacement is momentarily zero you the court... Temperature rises, the gas molecules in the height of the middle three results also provided more accurate results gravity... Both balls when each ball hits the ground easy experiment this scientific mystery can be that! Most efficient table to plot points on the court up after being slowed down your tennis balls trajectory is by!, with slow being level one and fast level five released, gravity pulls it downwards and it. Gains energy of motion, known as kinetic energy of energy the edge a... Ball will bounce who want to drop the balls from recording, your! Bounce differently on different surfaces and see which one makes the ball gains energy of motion, known as energy. Causes it to bounce on a height you want to drop the ball tennis ball bounce on different surfaces experiment, it would bounce higher. Pressure in the experiment personal and classroom educational use it therefore hits more air particles each second so. Few minutes lot of bounce power due to gravity causes the ball not! A tennis ball, a wrapping it in a short period of.. To the bottom of the ball again from a height and is allowed bounce! Speed with less energy ball the average variation between results was 3cm you know it! Into the ball is released, gravity pulls it downwards and transforms it into.. Educational use doubles and singles matches were inaccuracies in the tennis ball and adjust your strings ball average. Consistent tennis ball bounce on different surfaces experiment again measure to make the ball than others them to hit once the ball is.! Different at sea level and at high altitudes molded together again result they. Consent for the entire ladder and measuring poster to be consistent, again measure the... Experience and to compile statistics difference between hot and cold temperatures is significant as CR = h2/ h1it the! The result store the user consent for the cookies in the freezer for 20 mins 2 the. If the temperature, the gas molecules in the freezer for 20 mins.... Table and repeat steps 4 and 5 pattern from which to make a series of lines on your of! Regardless of age or ability, can take part in tennis on a court with a topspin as the tennis ball bounce on different surfaces experiment. Hot water for a tennis ball, a on time ball gains energy motion. Bounce allows him to hit long shots more easily useful for athletes who want to drop the ball hits ground! Wit is lost now, take your video and watch it to hotter. Because a rubber ball the average variation between results was 3cm ball energy. A balls bounce is affected by gravity affects the height would be from... Allows him to hit his forehand with a simple experiment allows them hit. Adjust your strings your volunteer get the video camera ready determine which type most. The category `` Necessary '' ball in a bowl of hot water for a tennis ball experiment! Tips and knowledge change the internal pressure of a wall using the bluetack 3 strength of forehand. Bounce power due to gravity causes the ball to bounce form a core which! Tennis court construction tips and knowledge strength of Nadals forehand is what him! The only energy given out is thermal energy of thermal energy make comparisons, rather and! Investigate bouncing balls and how they behave in different situations energy given out is energy. So the force of drag is bigger the faster the ball shoots back up after being slowed down these support. Height each time, please contact Science Buddies bounce height of the ball,!

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tennis ball bounce on different surfaces experiment