Stopping Distance, Science Assignment

Stopping Distance, Science Assignment

Year 10 Unicorn

Group Members: Garry Saju, Prince Sebastian, Steffan Kosky, Hazuki Horiuchi, Ellie AhnTeacher: Bradley Wilken

Weighting: 15%

Stopping Distance

Aim: What is the relationship between speed and stopping distance?

Introduction:

Background information on the topic including previous experimentsAverage Speed = Distance Travelled/ Time TakenDistance = Average Speed x Time

Acceleration = change in velocity/ time taken for the change

Previous experiments include (ADD THIS PRINCE)

Definition of uncommon termsDisplacement: A measurement of the change in position of a moving body; a straight line connecting the start and end points is specified in terms of length and direction.

Distance: A measurement of how far apart objects are.Efficiency: A measure of the useful energy output of an energy transfer.Instantaneous speed: the speed of an object at a particular moment.

Reaction time: The length of time it takes a driver to respond to a hazard.

Scalar quantity: A quantity, such as distance or time that has a size but not direction.

Speed: the rate of change of distance.

Vector quantity: A quantity, such as displacement or velocity, that has size and direction.

Velocity: The rate of change of displacement.

Variables that affect stopping distanceThe primary variable affecting the stopping distance will be the speed, due to the fact that the speed determines the stopping distance. Other variables will include the efficiency of the car (including braking systems and tires), the reaction time of the driver and whether the terrain the vehicle travels on is: A) on an incline. B) A smooth surface C) Coated in any slippery substances.Relevancy of this investigation to road safetyThis investigation is relevant to road safety because it is important for road users to be aware of safe stopping distance requirements. For example, the A.C.T. Road Ready Booklet (reference this GARRY) recommends leaving a three second gap between the vehicle in front during dry/sunny weather conditions, and leaving a six second gap in wet weather. It is also law requirement that automobile owners submit their car to pass an A.C.T. Roadworhy certificate, which proves that it is in safe condition to be operated on the roads. Road users having a thorough understanding of how speed, weather conditions, traffic spacing and car safety/brake/tire efficiency can affect their driving would help to reduce road-related fatalities.Hypothesis: The greater the speed, the greater the stopping distance will be. Stopping distance can be reduced by implementing efficient brakes and tires and ensuring the travelling medium is not covered with slippery substances; this is due to the fact that brakes cause friction, tires in good condition have better tread, which will slow speed dramatically, and slippery surfaces reduce the efficiency of brakes.Equipment: Stopwatch

Two people (one for recording times and one for riding the bicycle). 2 bicycles (one in good condition, {with good brakes and wheels}, and one in bad condition, {bad brakes and wheels}.

Measuring tape Cones (or something similar that may be used to mark locations).

Writing implements (paper and pen).

Experimental Design:

Method: The equipment was setup in an appropriate location as shown in the diagram above. Simultaneously the recorder hit the start button on the stopwatch and instructed the riding subject to start. When instructed to start, the riding subject began to ride their bicycle forwards (without any turning) until they reached the stopping cone, at which point they applied the brakes lightly.

When the bicycle passed the stopping cone, the recorder stopped the stopwatch.

The riding subject continued to lightly brake until the bicycle came to a halt. They then waited in this location for the recorder to use the measuring tape to determine the distance between the stopping cone and the bicycle (the stopping distance). The recorder then logged the stopwatch time and stopping distance on the paper.

The above steps were repeated several times, using different variables (the variables included using the bad bike, the riding subject travelling at a medium and fast speed, applying the brakes at a medium and firm pressure, not applying the brakes at all, and wetting the travel terrain with water). Each variable was tested three times as a minimum. After all recording was completed, the information on the paper/s was used to determine the average speed in each testing and the average stopping distance that correlated to that speed.Results: Quantitative Results: Table 1.A. Measurements of Stopping Distance (Bad Bicycle on dry terrain)Note: Formula for calculating average speed = Distance Travelled Time Taken

Therefore Average Speed = 50 metres Time Taken Test no. 1Test no. 2Test no. 3Average (combination of the three tests 3)

Riding Subjects SpeedBraking System Usage50 metres travel time (secondsAverage Speed (M/S)Stopping Distance (metres)50 metres travel time (seconds)Average Speed (M/S)Stopping Distance (metres)50 metres travel time (seconds)Average Speed (M/S)Stopping Distance (metres)50 metres travel time (seconds)Average speed (M/S)Stopping distance (metres)

SlowNo Brakes18.712.678617.372.888818.292.738718.122.7687

Light Brakes17.562.8533.817.812.813317.672.8333.217.682.8333.33

Medium Brakes 17.602.841518.012.7814.618.142.761417.922.7914.53

Firm Brakes 17.592.841.517.452.871.617.372.881.717.472.861.6

MediumNo brakes 11.254.4411211.184.4711010.964.5610911.134.49110.33

Light Brakes 10.754.6549.511.044.534911.704.274811.164.4848.83

Medium Brakes 11.634.3020.610.924.582110.604.722211.054.5221.2

Firm Brakes10.974.563.5511.554.333.611.284.433.5611.274.443.57

FastNo Brakes 7.536.64175.68.096.181707.586.60174.57.726.48173.37

Light Brakes 8.176.12103.57.616.571098.206.101037.996.26105.17

Medium Brakes8.256.0654.68.146.14558.146.1455.38.186.1154.97

Firm Brakes7.626.567.47.806.417.27.706.497.37.716.497.3

Table 1.B. Measurements of Stopping Distance (Good Bicycle on dry terrain)

Note: Formula for calculating average speed = Distance Travelled Time Taken

Therefore Average Speed = 50 metres Time Taken

Test no. 1Test no. 2Test no. 3Average (combination of the three tests 3)

Riding Subjects SpeedBraking System Usage50 metres travel time (secondsAverage Speed (M/S)Stopping Distance (metres)50 metres travel time (seconds)Average Speed (M/S)Stopping Distance (metres)50 metres travel time (seconds)Average Speed (M/S)Stopping Distance (metres)50 metres travel time (seconds)Average speed (M/S)Stopping distance (metres)

SlowNo Brakes13.503.70108.614.213.5210413.593.6810813.773.63106.87

Light Brakes13.943.574213.673.664413.763.634313.793.6343

Medium Brakes 14.423.471713.723.641814.333.4916.814.163.5317.27

Firm Brakes 14.283.502.1714.303.502.214.353.482.314.313.492.22

MediumNo brakes 7.436.731798.086.191767.626.561777.716.49177.33

Light Brakes 8.036.23958.206.10937.596.59957.946.3094.33

Medium Brakes 7.796.42467.526.65498.046.22447.786.4346.33

Firm Brakes8.365.986.17.846.386.88.276.056.28.166.136.37

FastNo Brakes 5.209.622034.5710.942104.3111.602134.6910.66208.67

Light Brakes 4.4111.341295.179.671285.309.431254.9610.08127.33

Medium Brakes4.9810.04815.019.9881.54.6010.87784.8610.2980.17

Firm Brakes4.6310.809.04.4011.368.54.4511.248.74.4911.148.73

Table 1.C. Measurements of Stopping Distance (Bad Bicycle on wet terrain)

Note: Formula for calculating average speed = Distance Travelled Time Taken

Therefore Average Speed = 50 metres Time Taken

Test no. 1Test no. 2Test no. 3Average (combination of the three tests 3)

Riding Subjects SpeedBraking System Usage50 metres travel time (secondsAverage Speed (M/S)Stopping Distance (metres)50 metres travel time (seconds)Average Speed (M/S)Stopping Distance (metres)50 metres travel time (seconds)Average Speed (M/S)Stopping Distance (metres)50 metres travel time (seconds)Average speed (M/S)Stopping distance (metres)

SlowNo Brakes18.232.9295.217.872.8094.118.332.7395.718.142.7695

Light Brakes17.482.8639.817.682.8340.417.892.7941.217.682.8340.47

Medium Brakes 17.582.382117.402.8720.517.152.9219.917.382.8820.47

Firm Brakes 17.412.873.217.602.843.417.242.93.017.422.873.2

MediumNo brakes 11.174.4812410.984.55123.210.904.59122.811.024.54123.33

Light Brakes 10.794.6360.210.434.7959.110.874.66110.74.6760.1

Medium Brakes 11.594.3130.211.774.2531.211.514.3429.711.624.330.37

Firm Brakes10.94.595.411.174.485.510.814.635.410.964.565.43

FastNo Brakes 7.496.68184.97.656.54187.37.216.93180.67.456.71184.27

Light Brakes 8.226.08114.78.036.23112.58.076.2112.88.116.17113.33

Medium Brakes8.126.1662.67.886.3560.68.276.0563.88.096.1862.33

Firm Brakes7.496.6810.47.396.7710.27.586.610.57.496.6810.37

Table 1.D. Measurements of Stopping Distance (Good Bicycle on wet terrain)

Note: Formula for calculating average speed = Distance Travelled Time Taken

Therefore Average Speed = 50 metres Time Taken Test no. 1Test no. 2Test no. 3Average (combination of the three tests 3)

Riding Subjects SpeedBraking System Usage50 metres travel time (secondsAverage Speed (M/S)Stopping Distance (metres)50 metres travel time (seconds)Average Speed (M/S)Stopping Distance (metres)50 metres travel time (seconds)Average Speed (M/S)Stopping Distance (metres)50 metres travel time (seconds)Average speed (M/S)Stopping distance (metres)

SlowNo brakes14.33.5120.913.763.63118.514.533.44122.414.23.52120.6

Light Brakes13.53.704914.033.5651.213.383.7447.113.643.6749.1

Medium Brakes 14.563.432814.453.4627.714.513.4527.814.513.4527.83

Firm Brakes 14.173.532.714.233.512.814.273.502.914.223.522.8

MediumNo brakes 7.206.941867.516.66191.47.027.12180.17.246.91185.83

Light Brakes 8.316.021098.066.20107.38.655.78111.78.346.0109.33

Medium Brakes 7.536.64547.466.753.77.496.6853.87.496.6853.83

Firm Brakes8.166.136.88.206.16.98.266.057.08.216.096.9

FastNo Brakes 5.109.802115.389.29213.84.8910.22209.65.129.77211.47

Light Brakes 4.7810.461425.029.96144.24.5710.94140.54.79

10.44142.23

Medium Brakes4.6010.87894.5111.0988.24.5710.9488.64.5610.9688.6

Firm Brakes4.4611.2110.14.5311.0410.24.5910.8910.34.5311.0410.2

Written Observations/Qualitative Results: Throughout the duration of the experiment it was usually quite simple to discern what the outcome would be before the result was measured or recorded. For example, the difference in the efficiency of the good and bad bicycle was very obvious. The good bicycle would accelerate faster than the bad bicycle; it would also travel at a faster speed than the bad bicycle when there was the same amount of energy output; and lastly, the good bicycle appeared to have far more effective brakes. Through simple observations based upon distance perception, it appeared that the two bicycles exhibited some similar characteristics: (1) When the brakes were used, stopping distance was decreased. (2) The faster the speed, the greater the stopping distance. (3) When the terrain was wet, stopping distance was increased. (4) The good bicycle would travel faster and brake more effectively than its counterpart.Graphs: Graph 1.A.Graph 1.B.

Graph 1.C.

Graph 1.D.

Discussion: Analysis of results(Just a note for you both before you start writing: dont use inclusive words (I, you, we, us, etc.) theyre not supposed to be used in scientific reports. Some teachers at school dont mind if you do, but just in-case they do, you should try and avoid these words. When you have to refer to the bike rider, use the names stated in the method or diagram.)(Basically describe what the graphs represent, because using the tables to describe our findings would be slightly laborious. Im not sure what the assignment means by comparing our mathematical relationship, maybe the relationship between speed and stopping distance??? Or it could be something else???I can remember that Pasunuri told us to explain everything that the graphs show, Ill let you be the judge of whether thats necessary or not)(Some of the significant findings from the experiment were: the greater the speed, the greater the stopping distance, brakes can decrease stopping distance, slippery or wet travel surfaces increase stopping distance)

(Compare the outcome of the experiment to the hypothesis)Reliability of results(You can say that our experiment was quite reliable given the materials that we had. However, possible errors would include: wind, human error, differing bicycle tire pressure between the two bikes,.).(Human error could have occurred when the time recorder both hit the start button on the stopwatch, and when they hit the stop button, just as the cyclist passed the stopping cone. It could have occurred due to the cyclist being late to begin riding and begin braking. And it could have occurred due to the cyclist misjudging the speed they were supposed to be travelling at (e.g. there would have been a slight difference each time the cyclist tried to ride at the slow pace).Under improvements you could like a large number of things. E.g. to improve the experiment, touch sensitive time recorders could be used. This means that as the bicycle passes the starting cone, it touches a trigger that automatically starts the recording process, and when it passes the stopping cone, the recording process is terminated. This would eliminate human error.

A device should be used to measure the exact speed of the bicycle, e.g. a speedometer. And to further improve the credibility of the experiment, a motor, which has a cruise-control setting could be attached to the bicycle, ergo ensuring that it always travels at the desired speed. This would eliminate the human error of misjudging speed.P.S. One other error and improvement would be that the bike should have been allowed to speed-up to the desired speed before the recording process began, therefore it would be travelling at the desired speed throughout the entirety of the time it takes for it to transition from the starting cone to the stopping cone. This can be seen as a slight error in our method (which didnt drastically effect/affect the final results (those two words confuse me???)) To improve this, the process of speeding the bike the desired speed beforehand should be added into the existing experiment. For this to be a part of the new and improved experiment, it would be required that the time trigger gates are installed, due to the fact that two timers are therefore required (one at the starting cone, and one at the stopping cone,) and having people do this would cause the inevitable human error to outweigh the benefit of pre-speeding the bicycle to the required speed.At the end of all this improvement and error stuff, it might do good to say that although all these improvements suggest good implications, the funding at ADHS is insufficient to supply such extensive equipment and the experiment that was conducted was therefore utilizing the available resources in a efficient and accurate manner. That way it seems like weve done a great job!Implications of this research

(Explain how the research shows that when a bicycle is well maintained, it performs far better. Presumably this is transferable to automobiles, and therefore if the vehicle is well maintained, it will be able to brake more efficiently). (State that this implies that it is crucial for safety that motorists maintain their cars to a safe standard, and it could result in saving lives that would otherwise be needlessly wasted in car crashes. Umm, you should also state that our research represents that it is less safe to travel in the rain {due to the fact that a wet road increases the stopping distance}).Conclusion: Bibliography1. Sleek Geeks Science Video ScriptFade in

Prince: Welcome to the domain of Sleek Geeks Science. I, professor Pince-ius Sebatian-ius, am to be your guardian angel of knowledge.

Voice: Okay, now shut up matey (Steffan, wearing tight sporty clothes and looking absurd, dashes in and pushes Prince out of camera screen-shot).

Steffan: (jumps up and down a few times like an athlete, then looks at camera). Okay mate-ies. Now there is a relationship (lots of expression) between speed and stopping distance. The greater the speed, the greater the stopping distance (show this in big white, bold writing at the bottom of the screen). For example (start doing actions to coincide with what is being said), when Imma runnin real fast, and I stop, it takes some time to slow down. But when Im jogging (stops), it takes zilch to stop.

Prince: (steps in front of camera). And now well give a real life, and accurate example. Steffan: (wavering/jostling a football above his head). Bring in the Calvary yall! Woo! Hut, two, three! (Sprints off with the football; does a 360 degrees spin and runs off.)

New scene

Camera shows a side view of Steffans driveway. Garry is on a bike on the driveway. His vision is aimed forward, toward his destination. Prince steps in to be positioned facing the camera, at the left side of the screen. He then becomes the prominent part of the shot. Sometimes as Prince talks, Garry will look toward the camera, and Prince will sometimes gesture towards Garry. Steffan is in the background, up on the stone wall, running around with his football, and making weird call signals, as well as doing odd manoeuvres)Prince: And now the highlight of our bliss evening together.

Steffan: Touchdown!

Prince: (looks a bit bothered by Steffans remark). We will show efficient resistance by having Garry, our brave young subject, (gesture to Garry, who looks at the camera confidently) ride this bike at a high speed. He will show this resistance by braking, thus proving how stopping distance can be reduced

Steffan: Tango, three four! Get the flanks! ARGG!Prince: Now lets delve in, and take a look at what scientific equipment we will be operating today. (Moves over to Garry, who now looks at the camera).So here we have a bike (gestures to bike). And next we have Garry of course. Now to operate the bike Garry will use this here, (points to pedals), and we call these Pedals.

And to operate the braking system (pauses for impact), he shall squeeze these triggers, which tighten these pads. The pads push against the wheel and slow the rate at which it revolves.

Prince: best of luck comrade Garry, waited long for this day you have (Garry nods).Garry begins to ride the bike at full speed/pelt and brake! says Prince.

Garry tries to brake, and makes a sound that is indicative of him being gobsmacked. It wont brake! Theyre broken! says Garry.

He then zooms down the driveway where the camera reveals there is an oncoming car. Suddenly the camera veers away from the sight, followed by a massive crashing noise.

Prince: Not again. Garry! Garry! Are you alright?

Prince: Someone turn this blasted recording device off Static

Fade in.

Show Garry in a hospital bed, wrapped in stiches.Steffan: Oh man, are you alright?

Garry: Oh yes Just dandy.

Prince: Well I hope you learnt something today.

Garry: Indubitably. Efficient stopping distance on a bike can be achieved through implementing a car, which travels perpendicular to the route of the bike The downside is (Looks down at his stiches and the crushed bike beside his bed). WellGetting hit by a car can really hurt.Prince: It sure can (nods to camera and smiles). It sure can.

(No real Indians were harmed in the making of this film).Script No. 2Filming location, the outdoor basketball court at ADHS

Props, probably one bike

Characters: The names I have used are just brief guidelines I dont mind who is which character, so if you want to swap your character with a different person, I dont mind) * Well need a cameraman (someone who isnt in our group).Clint Gregory: Prince

Clint Eastwood: Steffan

Marian Jeffries: Ellie or Hazuki (you two debate over it)Missy Jones: Ellie or Hazuki (you two debate over it, FYI, there is a huge contrast in the personality of the two girl characters).(Show Gregory outside near the oval, with nobody else inside the camera screenshot).

Cameraman: Alright youre on the air sir.Gregory: Oki Doki Sleek Geeks Viewers around the world. Today youre in for a treat as we prepare to interview some of the most prestigious figures of the Australian science community.

(Fade out, and fade in at the basketball courts location with Jeffries, Jones, Gregory and Eastwood (Eastwood is riding around on a bike)Gregory: Over there we have Jeffries and Jones, the masterminds behind the most recent scientific discoveries. (begins walking over to Jeffries and Jones).Gregory: Good evening professors.Jeffries: Hello

Jones: Hi

Gregory: My name is Clint Gregory; no doubt youve been expecting me?Jeffries: No.

(Gregory looks at the cameraman)

Gregory (whispers softly): You said you organised it.

Cameraman (whispers softly): Yeah, well You said you were giving me a raise.

(Gregory looks befuddled, then returns to look at Jeffries and Jones).

Gregory: Well I am here on behalf of Sleek Geeks Science to interview you both, to find out just why youre the snazzy sensations of the month.Jones: Okay, well it goes like this. When we were, like, 15 and 9 months, we decided to do this, like, experiment, like. And like 1 month later. Here we are! Like.Jeffries: I think what my colleague is trying to point out is that we have made a groundbreaking scientific discovery.

Gregory: Yes.

Jeffries: We have discovered the relationship between speed and stopping distance! Merely by using bicycles!Gregory: My god! This is the most exciting stuff Ive heard in my entire career! (Smiles widely/wildly at the camera)Jones: Yeah, man. Ill admit, it is some pretty serious shit.Jeffries: We have also summarised our findings in this short piece of paper, so that they can be understood by the more special members of our community.. (pulls paper from pocket) (Have the info displayed at the bottom of the screen as Jeffries reads it out, also have presentations on the screen of Eastwood riding the bike to coincide with what is being said).Jeffries: The greater the speed, the greater the stopping distance.Average speed equals distance travelled divided by time taken.

Wet surfaces increase stopping distance

Brakes that are well maintained will allow the moving bicycle to stop more effectively.

A well maintained bicycle can both speed-up faster, travel faster with less effort required, and stop faster than a bicycle that is poorly cared for.

Jones: And whats more exciting, is that these skills are, like, transferable to cars, like.

Jeffries: Thats right, our discoveries are universal. Cars respond to these phenomena in the same fashion. Gregory: I simply cannot believe my ears! Youll save millions of lives with these findings!

Jeffries: We already have.

Jones: Yeah, we like contacted the road authorities the second we discovered that there is a relationship between, like, speed and stopping distance. Like.

Gregory: The greater the speed, the greater the stopping distance, right?

(Both girls nod)

Jeffries; Correct

Gregory: So how did you discover all this?

Jeffries: Laborious research that is well beyond the capabilities of your puny little mind.

Gregory: Hmmm Highly offensive, but Ill ignore that remark.. So girls youre celebrities, whats next?

Jeffries: Well, I think I can see us sharing a Nobel Prize some time very soon. Once were Nobel Laureates, who knows, we may stumble upon even more terrific findings. Were like the Isaac Netwons of the 21st century, only, were girls, and therefore better.

Gregory: Terrific! Just terrific girls! (camera turns away so that it only shows Gregory). Well that was something amazing, wasnt it folks? And when we return after the break, well show you the exclusive footage of our cameraman, who went undercover to gain firsthand footage of these fantastic bicycle experiments whist they were being conducted.

(Camera screenshot shows one of the test-runs of the bicycle experiment. Suddenly the stopwatch recorder looks at the camera,

Stop watch man: Hey. What the hell is he doing here? (picks up a tennis ball or rock and throws it at the camera)

(The camera shifts from the scene as the cameraman turns to run. Yet the camera soon falls to the ground, as the object hits the cameraman.Stop watch man: Hazzah! I nailed him.)

(Camera screenshot returns to Gregory)

Gregory: Stay tuned.

(Any changes to the script are welcomed. Also, the only part that wasnt added, was how we found our scientific findings. Yet the rubric doesnt state that we have to include that, it only said that we have to summarise the findings. Which I think we did, kinda).