controlled variables in bouncing ball experiment
The distance along the ramp which the balls rolls. As the ball is falling toward the ground its Kinetic Energy is increasing because its speed is increasing. Is a bouncing ball an example of oscillatory motion? Read books, magazines or ask professionals who might know in order to find out the factors that affect the movements of a dropped ball. As the ball falls it hits against air particles. What is happening to the balls energy with each bounce? These are parts of the experiment that you try to keep constant throughout an experiment so that they won't interfere with your test. A) Using the graph above, find the displacement of the ball at 50 seconds. A ball falls from a height of 6 metres. This will be called the average of the middle three repeats. The last term can be the lowest height of the ball before it comes to an end as seen below. As the ball falls through the air, the Law of Conservation of Energy is in effect and states that energy is neither gained nor lost, only transferred from one form to another. The controlled variables in this experiment are the surface the ball is rolling on, the material the ball is made of, the size of the ball, the measuring devices being used, the distance the ball travels, and the method being used to release the ball each time, for example the position of the hand. Hence the final answer is: \(\text{Total distance} = 2 \cdot S_n = 2 \cdot 9.6 m= 19.2m\). Variables that may affect the bounce of a dropped ball are: You may study the effect of any of these variables on the bounce of a dropped ball. Therefore the ball dropped from the higher height must give out more thermal energy in order to end up with the same amount of energy as the other ball. A ball falls from 8 metres and rebounds to 52 percent of its previous height. Using the slope and graph, we can estimate that the ball would bounce to 0.75 m if dropped from 1.5 m and bounce to 1 m if dropped from 2 m. It is difficult to say with certainty that a ball dropped from 100 m would bounce to 50 m. That is because the heights we dropped the tennis ball from were all under 1 m, and at a much greater distance there may be other factors that would contribute to the bounce height. Will you pass the quiz? WebVariables: Height from which the ball is dropped Mass of the ball Material ball is made from External factors, i.e. If you did not observe a consistent, reproducible trend in your series of experimental runs there may be experimental errors affecting your results. This causes the amplitude of the height to reduce over time and eventually come to a stop due to friction forces like air resistance, which are assumed to be zero in an ideal scenario. Maybe you are reading a scale incorrectly, or maybe the measuring instrument is working erratically. 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. It is also good to calculate the coefficient of restitution of your ball using the formula CoR = v/v = sqrt(h/h). The force that is received by the ball from the ground from the collision causes it to rebound, which converts the potential energy to kinetic energy. The moving ball gains kinetic energy when it bounces, and loses potential energy as it falls. This would allow the actual coefficient to restitution to be calculated. The ball has reached its terminal velocity and cannot fall any faster (unless dropped in a vacuum). However, they only stretch for an instant before atomic interaction forces them back into their original, tangled shape and the ball shoots upward. For each run, a different amount of change in the variable is used. It shows that heights were recorded that exceeded the height that the ball would have reached had it been dropped in a vacuum. In the bouncing ball example, external forces such as air resistance are assumed to be zero. This is Newtons Third Law of Motion- for every action there is an equal and opposite reaction. This motion can be described using a geometric sequence, as the height of the ball after each bounce depends on the initial height from which the ball fell. For the lowest three points air resistance is approximately equal to zero due to the ball having a low velocity, as it was dropped from a low height, and therefore hits less air particles per second than a ball traveling at a faster speed. Variables Independent variable = drop height Dependent variable = bounce height Controlled variables = ball, surface, measuring tool. If you are new in doing science project, click on How to Start in the main page. Hence the formula for the sum of the infinite number of terms can be rewritten as seen here. Finally, we need to multiply the distance found by 2, as one bounce of the ball includes both a rise and fall. At that instant, how does the ball know how high it should bounce? A series of experiments can be done by changing one variable a different amount each time. The dependent variable is how high the ball bounces. Control variables include the type of ball, the surface that it is dropped onto and the size of the ball. 3. Testing reaction times can be investigated by dropping a ruler and seeing how quickly someone can grab it. The independent variable is the person who is trying to catch the ruler. The following is a college level project, but some grade 9 to 12 students can also complete this with no problem. Constants: the same person takes all of the measurements, the same materials are used in every trial. Set individual study goals and earn points reaching them. Adapted from Plangenhoef, Patterns of Human Motion. 2. WebWhat is a control? The higher the height from which the ball was dropped from, the higher the height to which it bounced. The format you use to write your bibliography may look like this: Are you ready for more advanced ball drop projects? It is from calculations using recorded data that tables and graphs are made. h1 = The distance between the bottom of the ball before it is dropped and the ground. An elastic surface such as rubber and a very hard surface such as concrete will result the highest bounce level. Materials:-Carbon Paper-Goggles-Golf The average variation between results was 3cm. 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. Tape the ruler to the wall. The ball rebounds to 38 percent of its previous height and continues to fall. A bouncing ball is an example of oscillatory motion as the ball is oscillating about the equilibrium position. We felt the magic immediately.". stay constant, results in an increase in m g h, stay constant, results in a decrease in m g h, The surface onto which the ball is dropped will affect the height to which the ball bounces because for any two objects that collide, the properties of both determine the percentage of the kinetic energy either possesses approaching the collision that is conserved subsequent to the collision taking place (Coefficient to restitution) discounting the effects of air resistance. By the time it reaches the floor, the ball is traveling quickly and it hits the floor hard. The bounce of a dropped ball has a direct relation with the air pressure inside the ball. Bounce/Release is the relation of bounce height to the release height. Prior to the sample task, students investigated investigated forms of energy and energy transfers and transformations. These are illustrated below. This would eliminate parallax error further. The mass of the ball will affect the height the ball bounces to because it affects the balls starting energy. This will help with your understanding of the investigation and lead you to make a possible hypothesis. Its a good idea to bounce it on a level surface, and dont release from too great a height, or while bouncing, the ball will wander away from the sound recorder range. Repeat your tests for each different type of bouncing surface and record the results in a table like this: Experiments are often done in series. Projectile motion is the motion of objects that are moving near the surface of the earth in a curved path due to the effect of gravity. This also proves the accuracy of the experiment. Problem: Hypothesis: Experiment: (Their ideas might include surface texture, colour, size, what its made of, squashiness, opacity, weight, air pockets, temperature, cost, shininess/dullness, hardness/softness, age, layers of materials.) WebAll experimental investigations involve variables. As elasticity and hardness decreases, part of the ball energy will be used to permanently dent or misplace or vibrate the surface, so ball will have less energy to bounce. The bounce of a dropped ball has a direct relation with the release height. 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 purpose of our lab was fulfilled. Our dependent variable was. The weight and material of the ball will be kept the same throughout the experiment by using the same ball. Use a uniform surface to drop the ball onto. Additionally we were able to practice reading a lab, taking data and making a graph. WebThis experiment,is an investigation into the maximum height of the bounce of a ping pong ball when it is first released.This is because of the unpredictability of the bounce not always reaching the same height.This we can assume their are many factors effecting the bounce of the ping pong ball.The following experiment will determine how different Hold the ball at 6 feet height and release it on a hard concrete surface. In reality, the ball experiences damping, where it loses potential energy and kinetic energy as it falls. For the higher heights the distance from h1 to h2 was almost a meter which meant it was difficult to get eye level from h1 to h2 to accurately in a short amount of time. The control variable is not part of an experiment itselfit is neither the independent nor dependent variable but it is important because it can have an effect on the results. As the ball flattening upon impact with the floor is not visible as it happens so quickly it would be almost impossible to measure the size of the ball on impact with the floor. it seems the ball is experiencing an oscillatory motion. The equipment necessary to generate these conditions was not available and as a result the results obtained were not one hundred percent accurate. StudySmarter is commited to creating, free, high quality explainations, opening education to all. Also the difference between the force of air resistance acting upon a ball travelling at 1ms-1 and the force of air resistance acting upon a ball travelling at 2ms-1 is far smaller than the difference between the force of air resistance acting upon a ball travelling at 20ms-1 and the force of air resistance acting upon a ball travelling at 21ms-1. Based on these trends, we can draw conclusions about the system under study. This help to greatly increase the accuracy of the experiment. You will then take your bounces and their respective time intervals to a spread sheet. This means that the faster that the ball travels the larger the force of air resistance upon it. Using the geometric sequence formula, the sum of the terms which are the heights of the ball after each bound: \(S_n = \frac{\alpha(1-r^n)}{1-r} = \frac{6m(1-0.38^5)}{1-0.38} = 9.6 m\). Try to find more information from physics or mechanics books. The maximum and minimum results were included when working out the variation between results however, seeing as the maximum and minimum results were produced by the experiment and are therefore part of the variation between results produced by the experiment. Procedure: One group member drops a tennis ball from a specific height, while the other group member notes how high the ball bounces. Independent Variable: The height from which the ball is dropped. A) scientific method. At 2ft, the basketball bounced 15 inches, the tennis ball bounced 12 inches, and the golf. A totally accurate experiment would have a variation between results equal to zero however an experiment that is totally accurate needs to be conducted under conditions where air pressure and temperature remained constant, error produced by the ball falling on different parts of the linoleum floor tile (which was not totally even and thus produces inaccurate results) and human error removed by dropping the ball onto a uniform surface and using machinery to record the height to which the ball bounced to. WebRamp and ball, controlled study lab report. Once the drag force equals the gravitational force all forces are equal and acceleration stops. This did not happen in my experiment however. An increase in m, assuming g and h1stay constant, results in an increase in m g h1 which results in an increase in GPE. Dependent Variable: The Bounce (How height is the ball going to Bounce) because of the The coefficient to restitution can be found out from a graph of, it follows the gradient of the graph change in h. . The acceleration on the ball is the acceleration of gravity, which acts downwards on the ball. This means it will be travelling the same speed when it hits the ground. What you have learned may allow you to answer other questions. Calculating the coefficient to restitution of ball hitting the floor: The coefficient to restitution can be found out from a graph of h1against h2. This denting extracts energy from the balls motion and stores much of it in the elastic surfaces of the floor and ball. This will be repeated five times, possibly more (for accuracy), for each height and the top and bottom results will be discounted. They identify variables to be changed, measured and controlled. Therefore of the GPE that the ball possessed at the beginning some energy is given off as thermal energy. TurnItIn the anti-plagiarism experts are also used by: King's College London, Newcastle University, University of Bristol, University of Cambridge, WJEC, AQA, OCR and Edexcel, Business, Companies and Organisation, Activity, Height and Weight of Pupils and other Mayfield High School investigations, Lawrence Ferlinghetti: Two Scavengers in a Truck, Two Beautiful People in a Mercedes, Moniza Alvi: Presents from my Aunts in Pakistan, Changing Materials - The Earth and its Atmosphere, Fine Art, Design Studies, Art History, Crafts, European Languages, Literature and related subjects, Linguistics, Classics and related subjects, Structures, Objectives & External Influences, Global Interdependence & Economic Transition, Acquiring, Developing & Performance Skill, Sociological Differentiation & Stratification. Also the ball flattening upon impact doesnt have to be taken into account whereas if one was measuring from the top of the ball as it hits the floor to the top of the ball before dropping it or at the top of its arc after bouncing or the middle of the ball as it hits the ground to the middle of the ball before dropping it or the middle of the ball at the top of its bounce then the fact that the ball flattens momentarily on impact with the floor would have to be taken into account. Even a specific ball may bounce different heights at different times or different locations. While a value of 1 indicates a perfectly elastic collision, a value of 0 indicates a perfectly inelastic collision. Several new questions may have occurred to you while doing experiments. By the time the ball comes briefly to a stop, most of its missing energy has been stored in its dented surface. A ball falls from a height of 3 metres. Please note that many online stores for science supplies are managed by MiniScience. " 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. 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. The difference between the predicted height and the actual height will provide evidence as to how air resistance affects the flight of the ball. changing air density, temperature The surface onto which the ball This means that KE is the same for both balls when each ball hits the ground. Data table 2 indicates that on average tennis ball bounced to a lower height than it was dropped from. It is also known as a constant variable or simply as a "control." If you have any questions or need more support about this project, click on the , If you are new in doing science project, click on . Create flashcards in notes completely automatically. Data Table 2: Average Bounce Height at Each Height: Graph 1: Height of Ball drop versus Height of ball bounce: Our data indicates that the hypothesis was incorrect. Therefore the height that it reaches is less high. The mass is cancelled out in the above equation, and we re-arrange with respect to velocity. How well a ball bounces deals with its coefficient of restitution. Create and find flashcards in record time. If the elastic potential energy is the same then the same amount of energy is converted back into KE and so the balls leave the floor at the same speed. When the ball rebounds, its stored energy reappears and it leaps higher into the air than it would have had you dropped it a shorter distance. Five repeats were done as it was deemed that an average of the middle three was reasonably accurate. The higher the ball goes, the more GPE it ends up with. Stop procrastinating with our study reminders. Several meter sticks for measuring the height of the bouncing ball or drawing a larger meter stick. Bouncing Ball Experiment Our simple experiment is to drop a ping pong ball weighed at 3 grams from a height of 1 metre then 90cm, 80cm, 70cm, Therefore the ball goes higher. For instance result 3 from 200cm was an anomaly but was not taken into account when taking the average of the middle three. In this experiment you will measure the bounce of a dropped ball for different release heights. At 3ft, the basketball bounced 20 inches, the tennis ball bounced. Charged Particle in Uniform Electric Field, Electric Field Between Two Parallel Plates, Magnetic Field of a Current-Carrying Wire, Mechanical Energy in Simple Harmonic Motion, Galileo's Leaning Tower of Pisa Experiment, Electromagnetic Radiation and Quantum Phenomena, Centripetal Acceleration and Centripetal Force, Total Internal Reflection in Optical Fibre. It pushes downward on the floor and the floor pushes upward on it. You may now be able to understand or verify things that you discovered when gathering information for the project. These stages are continuously repeated and shown in the sequence below. Working out the variation in results shows how accurate the experiment was. Your assistant will record the bounce. Your challenge will be to find a way to determine your balls e, and the initial height of the ball when you first dropped it. At the lowest point, the ball has its minimum potential energy, and the velocity changes from negative to positive. The last stage is the point at which the ball has reached its maximum displacement, decelerates, and changes the direction of motion from upwards to downwards. As the ball flattening upon impact with the floor is not visible as it happens so quickly it would be almost impossible to measure the size of the ball on impact with the floor. You will need an assistant, so one person will drop the ball and the other person stands about 20 feet away and records how high it bounces. Use the same point on the ball (top) or (bottom) when judging both the height This is correct unless the ball shows signs of reaching terminal velocity. The balls leave the floor at the same speed with the same amount of KE and so both balls reach the same height and end up with the same amount of GPE at the top of their bounces. Apparatus:Clamp stand, meter rule 2, table tennis ball, desk. Find out about the physics of a dropped ball. If the common ratio of the sequence is between 0 and 1, then the term r would approach zero. Is the measurement method questionable or unreliable? 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. B) If I heat up a tennis ball it will bounce high. Without a control you cannot be sure that changing the variable causes your observations. A ball that is dropped in air however is subjected to air resistance which affects the height to which it bounces. The experiment was conducted as the method (below) states. In a real-life scenario, the ball will eventually stop moving due to external forces such as air. The balls are shown at rest, about to bounce back up. For example, we could have used a ruler on the top to help us read how high up the tennis ball bounced, and we could have made sure the partner taking measurements did so from a consistent height. h1will start at 2m and then move down in intervals of 10cm to 10cm. Click Create Assignment to assign this modality to your LMS. The first thing to check is how you are making your measurements. So once you know how to calculate KE and GPE, it is simple to calculate their sum, E. KE of a dropped ball changes as it falls. Find the total distance of travel until the ball hits the ground for the 8th time. Use a racquetball, a golf ball or any kind that bounces well and makes a nice crisp sound when it bounces. Discuss specifically how you developed your e and initial height values. However when the ball is dropped from a relatively low height, drag 0. An alternative method would be the measuring person holding a video camera level with the approximate height that the ball reaches after bouncing and videoing the ball reach the top of its arc. The coefficient of restitution is the ratio of the final to the initial relative speed between two objects after they collide. As the height from which the ball was dropped from was increased, the GPE energy that the ball possessed before being dropped also increased. This applies to a ball falling in a vacuum. WebLearn how to identify types of variables in a simple experiment with bouncing balls. 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. Controlled Variables: Bouncy ball used, surface bounced off of, technique in which ball was dropped (initial height was measured from base of ball). Also the ball flattening upon impact doesnt have to be taken into account whereas if one was measuring from the top of the ball as it hits the floor to the top of the ball before dropping it or at the top of its arc after bouncing or the middle of the ball as it hits the ground to the middle of the ball before dropping it or the middle of the ball at the top of its bounce then the fact that the ball flattens momentarily on impact with the floor would have to be taken into account. This means that the faster that the ball travels the larger the force of air resistance upon it.