Annex A - Group Research Proposal

Investigative Skills in Science

 Research Proposal Form

 

Project Title: Investigation of the effect of different surfaces on the bounciness of a tennis ball.

 

Class

S2-06

Group:

J

 

SN	Name of student	Email
1	Ethan Chan Song Yi	ethan_chan_song_yi@s2020.ssts.edu.sg
2	Goh You Jun	goh_you_jun@s2020.ssts.edu.sgn
3	Kottaimuthu Shrinithi	kottaimuthu_shrinithi@s2020.ssts.edu.sg

 

Type of research:
X	Test a hypothesis: Hypothesis-driven research
	Measure a value: Experimental research (I)
	Measure a function or relationship: Experimental research (II)
	Construct a model: Theoretical sciences and applied mathematics
	Observational and exploratory research

 

Category of research:	Sub-category:
Physics and Astronomy (PHYS)	Physiology
Reference	https://www.societyforscience.org/isef/categories-and-subcategories/all-categories/

Research Plan

 

Project Title: Investigation of the effect of different surfaced on the bounciness of a tennis ball.

 

1. INTRODUCTION: 

        Tennis is a racket sport that can be played individually against a single opponent (singles) or between two teams of two players (doubles). Each player uses a tennis racket strung with cord to strike a hollow rubber ball covered with felt over or around a net and into the opponent's court.

This investigation aims to test the effect of the bounce or change in elastic potential energy within a tennis ball when dropped on different surfaces.

Modern tennis balls must conform to specific criteria for size, weight, deformation, and bounce bars to be approved for regulation play. The International Tennis Federation (ITF) defines the official diameter as 6.54–6.86 cm (2.57–2.70 inches). Balls must have masses in the range 56.0–59.4 g (1.98–2.10 ounces). Yellow and white are the only colours approved by the ITF. Most balls produced are a fluorescent yellow known as "optic yellow", first introduced in 1972 following research demonstrating they were more visible on television.

        Tennis balls are filled with air and are surfaced by a uniform felt-covered rubber compound. The felt delays flow separation in the boundary layer, which reduces aerodynamic drag and gives the ball better flight properties. Often the balls will have a number on them in addition to the brand name. This helps distinguish one set of balls from another of the same brand on an adjacent court.

There are different types of surfaces that we are testing; clay, turf, concrete, wood, grass, and tile.

 Clay courts affect how the ball spins and is returned. Clay tennis courts favour players who can play defence. Players preserve more energy playing on a clay court since they can slide into their shots instead of coming to a complete stop.

A synthetic Turf Tennis court is a surface composed of polypropylene or polyethene grass fibres infilled with a specially graded sand top dressing.  The resulting surface is slower and more forgiving, much like a clay court, without the maintenance and foul weather issues inherent with them. The specially designed sand filled surface holds firm, even after a heavy rain, reducing the wait time to minutes instead of hours. The sand level and size may be adjusted to the customers' preference for ball speed and foot play. A court with more sand will be slower and create a slip and slide effect more like a clay court. 

In a concrete tennis ball court, the ball travels at speed slower than on Grass Courts but faster than Clay Courts, and the bounce of the ball is high due to the hard surface. Moreover, the ball's bounce is very predictable as the surface is very flat and easy to maintain.

This will allow future tennis players understand the difference in techniques depending on the surface 

When testing on wood, since wood is hard and rough, a ball is predicted to bounce higher than the same ball when bouncing off a clay surface. Since it is partially energy absorbent, the ball may not bounce higher than the same ball bouncing off concrete. 

When testing on grass, since grass is soft, and it is very energy absorbent, the ball will bounce very little compared to the same ball bouncing off other surfaces.

2. RESEARCH QUESTION(S):

 

2.1 Research question being addressed

Which surface will a tennis ball bounce the highest?

 

2.2 Hypotheses

The ball will bounce the highest on the concrete surface.

The ball will bounce the least on the grass surface.

 

2.2.1 Independent variable

  

The surface the ball is dropped onto.

 

2.2.2 Dependent variable

 

The dependent variable is the height the ball bounces to.

 

2.2.3 Controlled variables

 

(a) Height the ball is dropped from (e.g. 1.0m )

(b) The size of the ball 

(c) The shape of the ball

(d) The material of the ball

(e) The weight of the ball

(f) The manufacturer of the ball 

(g) The force used on the ball when it is dropped, make sure its 0 

3.    Method

 

3.1 Equipment list:

 

- Tennis ball

- 2 Retort stands

- Tables or any ground that has different surfaces

- Lightweight String

- Mini Trap Door

- Camera or Phone with retort stand or tripod

 

3.2 Diagrams

Figure 1: Experimental setup

3.3 Procedures:

1. Go to a location with no wind and a concrete floor.

2. Attach the clamps at 0.5m on the retort stand

3. Place a trap door directly horizontal to the stand.

4. Place a 1m ruler next to the retort stand.

5. Attach strings from the trap door to the top of the retort stand to prevent the trap door from closing

6. Place the ball on the trapdoor.

7. Ensure that the ball is not rolling

8. Start the video and cut the string.

9. Record the height by using the video to estimate

10. Repeat step 5-9 two more times

11. Repeats steps 5-10 on each surface tested

 

3.4 Data Analysis: 

 

1. Find the average measurement ( how high the ball bounces ) for each surface.

2. Write and type the measurements into a table, each column for a different surface, and each row for the height of bounces.

3. Plot a histogram of rebound height against the type of surface.

4. Compare the histogram and find the best surface. 

 

 

4. Risk, Assessment and Management: 

Table 1: Risk Assessment and Management table

Risk	Assessment	Management
The retort stand may fall over, and the trapdoor may hit our feet.	Medium	Add some weight to the retort stand to prevent it from falling.
The ball might be released and drop on the feet of someone.	Small	Stand a safe distance away and keep people out.
The ball may rebound and hit the eye of the person recording the video of the bounce.	High	Have the person who is videoing the experiment wear safety goggles
The retort stand might trip someone who walks by	Medium	Keep people away

5. References: 

 

Tennis Uni. (2020). "Tennis Ball - The Ultimate Guide" Tennis Uni Retrieved January 15, 2021, from https://tennis-uni.com/en/tennis-balls/

Brungi, P. (2014). "The Tennis Ball Experiment" Independent Science Research Project Retrieved January 15, 2021, from https://prathushascienceresearchproject.weebly.com/conclusion--discussion.html

Michele, M. (2009). "What are ping pong balls made of?" Sportsrec Retrieved January 15, 2021, from https://www.sportsrec.com/what-ping-pong-balls-made-4923247.html

 

6. Bibliography: 

PubMed (2003). Bounce of a tennis ball: Retrieved 16 January 2021 from https://www.researchgate.net/publication/10713473_Bounce_of_a_tennis_ball

Fred Watkins (2011). Science Project The height of a balls bounce on six different surfaces: Retrieved 16 January 2021 from https://www.youtube.com/watch?v=b1FTzuywf10

ActiveSG (2020). Differences between tennis courts: Retrieved 16 January 2021 from https://www.myactivesg.com/Sports/Tennis/How-To-Play/Tennis-Facts/Differences-between-tennis-courts

APT (2012). Types of Tennis Courts: Retrieved 16 January 2021 from https://sportsbyapt.com/types-tennis-courts/#:~:text=Tennis%20has%20a%20long%20history,offers%20unique%20challenges%20to%20players