This applies to a ball falling in a vacuum. Use the pencil and ruler to connect the incoming and outgoing trajectories of the marble to the point where the marble bounced off the wood. These polymers are tangled together and stretch upon impact. Experiment 2 is for testing the effect of air pressure. We use the conservation of energy. Use a racquetball, a golf ball or any kind that bounces well and makes a nice crisp sound when it bounces. WebBouncing balls. However, the tennis ball we used may be a very old one, and to definitely prove that our hypothesis is wrong for most tennis balls we would need to repeat the experiment with many different tennis balls. This experiment would provide me with more results that are relevant to the experiment that I have already conducted. 70% is retained. The formula for gravitational potential energy is PE = mgh where m is the mass of the ball measured in kg, g is the gravitational acceleration constant of 9.8 m/se c2 , and h is the height of the ball in m. As the ball falls through the air, the potential energy changes to kinetic energy. Repeat your tests 9 more times and each time lower the release height for 6 inches. This is because it is easiest as the figure read of the meter rule is the result. The longer it takes to stop, the higher it bounces to. Will you pass the quiz? WebBouncing Ball Experiment - Free download as Word Doc (.doc / .docx), PDF File (.pdf), Text File (.txt) or read online for free. This means for the ball to reach terminal velocity the drag force has to be bigger and for the drag force to be bigger the ball has to fall faster (so that more air particles hit the ball every second). In this experiment the only variable that we modify is the type or flexibility of bounce surface and we keep all other variables unchanged. Working out the variation in results shows how accurate the experiment was. Maybe you are reading a scale incorrectly, or maybe the measuring instrument is working erratically. This would provide evidence on how the height from which the ball is dropped from affects the height to which it bounces without air resistance. Drag is a squared function of velocity and therefore as the ball drops drag increases a greater amount each second. The push which the ball receives from the floor at the moment of impact causes it to bounce up from the surface. 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. That height fraction is equal to the fraction of energy that the ball successfully stored and returned during its bounce. Temperature will not affect the balls bounce either as the experiment will be conducted at room temperature, thus not allowing the floor to get cold and in doing so alter its affect upon the ball on impact. C) Frozen tennis balls will not bounce as high. If you are new in doing science project, click on How to Start in the main page. 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. D) If I freeze a tennis ball, then it will not bounce as high. Tape the ruler to the wall. List three. Design an experiment to test each hypothesis. This would allow one to find the terminal velocity of the ball. As the ball is falling toward the ground its Kinetic Energy is increasing because its speed is increasing. The moving ball gains kinetic energy when it bounces, and loses potential energy as it falls. Have all your study materials in one place. These are parts of the experiment that you try to keep constant throughout an experiment so that they won't interfere with your test. We can go back to our table of velocities, square each one, then multiply by 1/ 2 * 0.044 kg to find the kinetic energy at each moment. Aim:To find out what affects the height to which a ball bounces. Calculating the coefficient to restitution of ball hitting the floor: The coefficient to restitution can be found out from a graph of h1against h2. The ball weighs exactly 2.5g. Several meter sticks for measuring the height of the bouncing ball or drawing a larger meter stick. tennis and baseball) includes the CoR test. 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. WebControl variables include the size of pots, the type of soil and the position in a room. The The bouncing ball example is an example used to study, A bouncing ball in an ideal scenario will continue this oscillatory motion. It is used to determine what the variable changed. The sum of the two, mechanical energy, stays the same ( is conserved.). Problem: Hypothesis: Experiment: It is always good to have an explanation for choosing any hypothesis. Therefore the heavier the ball is, the faster its terminal velocity. A series of experiments can be done by changing one variable a different amount each time. This help to greatly increase the accuracy of the experiment. B) If I heat up a tennis ball it will bounce high. where m is the mass of the moving object, and v is the velocity of the moving object. will differ from the height that the ball would have reached had it been dropped in a vacuum. WebDrop the ball from the line between cinder blocks/bricks to make the measurements more accurate. Review each step of the procedure to find sources of potential errors. Identify your study strength and weaknesses. The slope of the line in graph 1 was found to be 0.5. This is correct unless the ball shows signs of reaching terminal velocity. It was difficult to get down to the exact level of the blue tack seeing as it meant lowering your entire upper body in the short amount of time taken for the ball to hit the floor and rebound again to get your eye level from h1 to h2 (where the blue tack was stuck, approximately). The ball then rebounds: it undents and tosses itself up into the air to a good fraction of its original height. WebThe scientific method consists of five steps: -Observation/research: The first step is to research and collect as much background information on your chosen question as you can. 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. You measure this response, or record data, in a table for this purpose. Is the measurement method questionable or unreliable? WebPhysics Lab 1 - Bouncing Ball - Hardik December 2019 PDF Bookmark This document was uploaded by user and they confirmed that they have the permission to share it. 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. Following are some sample information that you may find: Everyone has played with balls that bounce, but few people truly understand the physics behind a bouncing ball. For a perfectly elastic bounce (the ultimate super ball), e =1; and for an inelastic bounce (like clay dropping on the floor), e =0. This also proves the accuracy of the experiment. Either the coefficient to restitution that was worked out is incorrect, which would mean that the first three results are inaccurate or subsequent results were inaccurate. This is impossible. With no net force, the acceleration = 0 and the ball falls at a constant velocity. This will help with your understanding of the investigation and lead you to make a possible hypothesis. For example a regulation tennis ball is dropped from about 1 meter. Set individual study goals and earn points reaching them. When you drop a ball from a greater height, it has more kinetic energy just before it hits the floor and stores more energy during the bounceit dents farther as it comes to a stop. WebWhat is a control? The balls are shown at rest, about to bounce back up. Stop procrastinating with our smart planner features. Therefore the results are valid. of the users don't pass the Bouncing Ball Example quiz! 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 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. So if we double the release height, we will get double bounce height. It is also known as a constant variable or simply as a "control." The Graph on page 23 shows that all of the results were very close together. Do you think e is constant for your ball? 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). Independent: - Type of surface the tennis ball is dropped on. It is always important for students, parents and teachers to know a good source for science related equipment and supplies they need for their science activities. WebControl Variable: Simple Definition. In this experiment there are FOUR VARIABLES. This will be repeated five times, possibly more (for accuracy), for each height and the top and bottom results will be discounted. This means that the faster that the ball travels the larger the force of air resistance upon it. 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. An average will then be taken. If the ball is elastic in nature, the ball will quickly return to its original form and spring up from the floor. If a ball reaches terminal velocity at 20cm from the floor when dropped from 2m, it will reach terminal velocity at 10cm from the floor when dropped from 1.9m. The CoR can be measured directly by velocity measurements but often it is handier to measure the height of rise of the ball after it bounces relative to the height that it fell. It provided me with five repeats so that the maximum and minimum results could be discounted and a reliable average could be taken. 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.