Science Project

[TAL]

My daughter up to the 2nd grade has done a class project with the whole class involved...

She this year is in the third grade and it is time for individual student science projects ...

I don't want to suggest something to hard for her , but I was thinking of suggesting maybe along the lines of running two 4 inch, 2 ounce pine wood derby cars and taking 1 ounce of tungsten for each car and compare simmilarities and comparison of weight placement...

Assuming both cars will start out identical in wood weight, wheel placement, pretty much identical car preps and start them both out at 2 ounces plane with no weight's for the first run...

Also when I ran the idea past her last night she seemed very interested...

But when I gave her an example such as if they weigh the same which will win ( assuming both cars are equal in creation and in general)...

She answered ; they should be about the same...

Then when I asked her if one was heavier which would win ; she answered the heavier one....

Then I described the issue of what if one had the weight up front and the other had the weight in the back ; she answered the one with the weight in the back...

I told her they are still the same weight though and asked should'nt they still be the same in speed...

I then asked her why did she think that and she thought a moment and said because it has a hoter motor and also described 2 or 3 other type of terms...

What would be some of the correct terms for what were doing???

Momenam, force , weight gain???



We have a timer (micro wizard) that will display times, and may add 1 ounce weight to 1 car and run, and then add 1 ounce to other car and run , and place weight's in different places on the car...

Maybe like 1 weight in the front on 1 car and the other weight maybe in the center of the other car midway...

I was thinking maybe a 16' running track (plus stoppers) with a 2 or 3 foot lift at starting gate...

Does anyone have any ideas or suggestions that may help us in this matter???

[Cory]

1. No two cars are exactly the same. Thus, by using two cars you are introducing an unnecessary uncontrolled (or not totally controlled) variable. I suggest using a single, configurable car.

2. If possible, you may want to make your starting gate height somewhat modifiable. A higher gate means less separation between designs but more consistent results. You want to find a good balance between these two goals before you start data collection. (I think 3 feet might be a bit high for 16' track and 5 oz car.)

3. Do multiple runs for each configuration that you test, as many as six or eight. Throw out the high and low and then average.

4. Relube and spin in (either with a dremel or with several spin-in runs) before each set of runs. The first few runs after applying graphite lube will be a bit slower unless you spin-in the lube.

5. Prevalidate your track setup. With a decent track, you should be able to run six or eight heats (after spin-in, of course!) with all the times within 10 or 15 milliseconds of each other -- you might do better than that, but that's a reasonable goal.

6. Be wary of track shifting. This can significantly affect times. In fact, I would recommend establishing a baseline configuration for the car, e.g. weight in the middle For each experimental configuration, do a baseline set, then the experimental set, then another baseline set. The two baseline set averages should be within some nominal limit -- if not then start over because you must have changed something about the car or the track, thereby invalidating the experimental set.

You can find more (possible helpful) comments here:

http://members.cox.net/pinehead/exper.html

[pwdarchitect]

I have a bit of advice for you within the whole science fair thing since my kids have done very well at the school and regional science fairs each year.

Presentation is everything! The judges hardly get to read all of the pieces within each of the projects so making the project "stand out" from the rest of the science fairs is the key. Also since obviously you found this site somehow, do a little search on the internet for science fairs projects. You will want to make sure that you have all of the requirements for the project but go above the required items and put in things like the independent variables, dependent variables, graphs, etc. You will want to make sure that you get enough data through more than one test for each of the setups.

Good luck with your experiment and make this a fun learning experience for your child.

J

[gpraceman]

MaxV does have a "Pinewood Wizard" car kit that is great for doing experiments with. http://www.maximum-velocity.com/kits.htm#wizard

[TAL]

1. No two cars are exactly the same. Thus, by using two cars you are introducing an unnecessary uncontrolled (or not totally controlled) variable. I suggest using a single, configurable car.

Makes since, But then again I could do 2 test in one shot; Keeping the 2 cars seperate, You know just for fun...

2. If possible, you may want to make your starting gate height somewhat modifiable. A higher gate means less separation between designs but more consistent results. You want to find a good balance between these two goals before you start data collection. (I think 3 feet might be a bit high for 16' track and 5 oz car.)

We have an aluminum track with a 4 foot high starting gate that we will have to figure out how to lower and like you say adjustable in height some what and were planning on having a 4 inch 2 ounce car with 1 onuce of tungsten to shift around so it would be a total of a 3 ounce car...

I suppose we can always add another 8 foot to the track for a total of 24 foot... We have 40 foot available...

Far as relubing, what would be your opinion on not useing lube for the initial testing until the very last test for a big big speed improvement, cause I'm thinking we are working with weight shifting and maybe save the friction demos and testing for maybe next year if things go well this year...

Plus I 'm thinking the graphite may be a no no in a public school venue for demo purposes...I really don't know yet... My first year ever helping with the decision of a school science project...

[TAL]

I have a bit of advice for you within the whole science fair thing since my kids have done very well at the school and regional science fairs each year.

Presentation is everything! The judges hardly get to read all of the pieces within each of the projects so making the project "stand out" from the rest of the science fairs is the key. Also since obviously you found this site somehow, do a little search on the internet for science fairs projects. You will want to make sure that you have all of the requirements for the project but go above the required items and put in things like the independent variables, dependent variables, graphs, etc. You will want to make sure that you get enough data through more than one test for each of the setups.

Good luck with your experiment and make this a fun learning experience for your child.

J

Sounds like really great advice and congrates on your kids jobs well done ...

I'm sure it really warms your heart to see them doing really well...

I'm new to the science project thing just as my daughter is too...

Do you think this could make a great project and be presented in a quality fashion???

[TAL]

MaxV does have a "Pinewood Wizard" car kit that is great for doing experiments with. http://www.maximum-velocity.com/kits.htm#wizard

Interesting kit...

I may proceed with that ...

We will be using your gprm software and are wondering is there some way to run one car like in race format and keep it on a single lane for the stats...and maybe do a round of 6 heats for each weight placement simulation and use the results for the data...

Also, if we could use 2 seperate cars and keep them in the desinated lanes...For example ;Test car one will do all 6 heats in all 6 rounds and remain in lane 1 throughout the intire test with test car #2 in lane 2 through out the intire test...

Is the gprm software cabable of doing that???

[pwdarchitect]

I have a bit of advice for you within the whole science fair thing since my kids have done very well at the school and regional science fairs each year.

Presentation is everything! The judges hardly get to read all of the pieces within each of the projects so making the project "stand out" from the rest of the science fairs is the key. Also since obviously you found this site somehow, do a little search on the internet for science fairs projects. You will want to make sure that you have all of the requirements for the project but go above the required items and put in things like the independent variables, dependent variables, graphs, etc. You will want to make sure that you get enough data through more than one test for each of the setups.

Good luck with your experiment and make this a fun learning experience for your child.

J

Sounds like really great advice and congrates on your kids jobs well done ...

I'm sure it really warms your heart to see them doing really well...

I'm new to the science project thing just as my daughter is too...

Do you think this could make a great project and be presented in a quality fashion???

I think that it can be done and be great. It's all up to how much research into the whole science fair project thing you do.
Last year my son got first place at the regional fair by doing a project that was centered around what effects certain things have on a person's driving ability like eating, talking on a cell phone, tuning your radio station.
Daughter did her's on which ice cream melted faster, an expensive brand or a more enconomical brand, also taking the overall award for her grade level. The test were done in such a matter that we had enough different brands of ice cream, 7 brands I think, that we were eating ice cream for weeks after.

Another thing to think of is a catchy title for the project, colors for a background, and good pictures that shows your steps.

Try this site: http://school.discovery.com/sciencefaircentral/

Jim

[gpraceman]

We will be using your gprm software and are wondering is there some way to run one car like in race format and keep it on a single lane for the stats...and maybe do a round of 6 heats for each weight placement simulation and use the results for the data...

You can always set the software for a 1 lane track and use the Lane Rotation scheduling (though, it is a short rotation ).

Also, if we could use 2 seperate cars and keep them in the desinated lanes...For example ;Test car one will do all 6 heats in all 6 rounds and remain in lane 1 throughout the intire test with test car #2 in lane 2 through out the intire test...

To do this, you would need to build the schedule manually. In the racing screen, you can click on the Manual Heat button and select cars for each lane and add the heat. Keep adding heats like this while keeping the same lane assignments.

[Stan Pope]

There is a small "gotcha" lying in wait for those who move weights around in a single frame. The friction contribution by each wheel is controlled by the amount of weight it is carrying. If the front wheels have lower coefficient of friction or are better aligned, then your experiment may show that moving the weight back is detrimental! How do you discover that this has occurred? Better yet, how do you lead your student to discover that this has occurred? And, how do you lead them to discover the antidote?

For your info, think "schizophrenic car" ... one that is front/back symmetric! And assure that the car is aligned to run well either direction. I'll leave arranging the "discovery process" for your student up to you.

[Cory]

Makes since, But then again I could do 2 test in one shot; Keeping the 2 cars seperate, You know just for fun...

Your choice, obviously. Using two different lanes introduces yet another uncontrolled variable.

Far as relubing, what would be your opinion on not useing lube for the initial testing until the very last test for a big big speed improvement, cause I'm thinking we are working with weight shifting and maybe save the friction demos and testing for maybe next year if things go well this year...

Plus I 'm thinking the graphite may be a no no in a public school venue for demo purposes...I really don't know yet... My first year ever helping with the decision of a school science project...

I predict your times will be significantly less consistent without lube.

http://members.cox.net/pinehead/expres1.html

Compare the variance of unlubed runs from test 1 with those of other tests. This is why I did this test first.

If you think long and hard enough, I think you'll conclude that it is impossible to alter weight placement without affecting other aspects of a car's performance. Even though it's an improvement over moving weight back and forth in a non-symmetric car, Stan's symmetric car will not run exacly the same forwards and backwards. There is always a "gotcha".

But again, it's your choice. The goal is to get a level of scientific rigor, without going overboard, that yields data which strongly supports your conclusions and which pleases the judges of a 3rd grade science fair. It's up to you to decide exactly where "overboard" is.

[Stan Pope]

If you think long and hard enough, I think you'll conclude that it is impossible to alter weight placement without affecting other aspects of a car's performance. Even though it's an improvement over moving weight back and forth in a non-symmetric car, Stan's symmetric car will not run exacly the same forwards and backwards. There is always a "gotcha".

Exactly right, as usual!

You can get some measure of the symmetric test car's "alignment symmetry" by comparing runs with the weight centered.

You get some measure of the friction symmetry by comparing runs with the weight off-center but same distance up hill from the starting peg.

The value of the symmetric car is that it helps isolate and quantify big contributors to error (or uncontrolled variance) in the results.

This is a concept to which I've tried to lead some of my charges. So far, I have been unsuccessful.

[Go Bubba Go]

TAL:

I don't have a lot of time right now, but here are some loosely organized thoughts on terms, etc.

1) Regarding terms - one of the terms that you are introducing with varying weights and weight placements is "Potential Energy".

2) Remember these are 2nd graders. Use exaggerated props to show principle and then demonstrate/confirm findings with the car. Example: For Potential Energy, use a "brick-o-penci-miter" (make up some name for fun that you think they will like and that "sounds" scientific). Get a 3 foot piece of string and tie a brick to one end and a pencil to the other. "Offer" to conduct a test by holding the "brick-o-penci-meter" just above one of their feet and letting it fall. Ask them which they would prefer, you hold it from the pencil end so that the brick drops from barely above their foot and the pencil drops 3 feet, or you hold it from the brick end so that the pencil drops from barely above their foot and the brick drops 3 feet. Intuitively they will know that even though the "brick-o-penci-meter" weighs the same either way, that the arrangement of the weight before you drop it makes a big (painful) difference. Then apply that principle to the car. Have two heavily "lopsided" cars (one with extra weight in back, other with extra weight in front), and ask which they think will run faster - more weight "higher up" in the rear, or more weight lower down in the front? Review their "conclusions" from the "brick-o-penci-meter"? Properly led through questions, they will make the connections about translating weight placement into added Potential Energy (resulting in added pain in one example and added speed in the other) one step at a time, nearly on their own.

3) Do not constrain your car design to fit Pinewood derby rules (5 oz., 7 in. length, etc.) While pineheads might get excited about a half car length victory, 2nd graders will not. Try to exagerrate the differences between the cars (longer wheelbase to enhance weight placement difference, greater weight added (5 or 6 oz. instead of 1 oz.) to enhance weight vs. unweighted difference) to increase the "wow, that slow car really got spanked" factor. This will also help to ensure that other minor differences between the cars don't "trump" the one difference you are trying to isolate and demonstrate.

4) Make sure you have throughly practiced and tested the outcomes with your 2nd grader. As you work through it with your own kid, you can spot gaps in your (their) presentation that might need to be adjusted to better "reach" 2nd graders. This is especially important if you are trying for a teaching (i.e. lead the audience to figure out results on their own, then see confirmation) rather than a showing (i.e. let me tell you and show you, you just watch) presentation. The practice will also build confidence in your 2nd grader if they are to conduct the presentation themselves.

Sorry I don't have time for more or to better organize the above.

p.s. For other aspects of Potential Energy, use a modified "brick-o-penci-meter". Just an empty bucket that you can place weight in (or not) to demonstrate impact of adding weight to PE i.e. "would you rather I drop this bucket on your foot while empty, or with these 3 bricks added first?". "What would be the difference?" "So which has more potential energy" If you have the time, you can demonstrate each element first with the "big toys" and subsequently confirm and show the effect on a test car. Help them to learn how to "apply" what they already intuitively know.

[Teeeman]

Suggest keep it simple enough to give value to the age group?

Suggest to focus on 2 things:
momentum = mass X velocity
potential energy (change in height)

For momentum, demonstrate how a car that is light can start on a ramp and stops on the flat (short of the finish line)… take the same car, add mass (weight) and repeat from same release height… car should go further on flat (more momentum)… again the free roll stop should be short of the stopping point.
This demonstrates how momentum helps keep things going.
(the sharper kids may realize the heavier car should be harder to start but moves down the ramp about the same… that might be a side-topic for the really interested kids on acceleration)

Pot En -> just demonstrate different release heights, again free roll stops on flat to show difference… use same car, same mass

If the car needs it, add some friction to be sure it stops on the flat.

If your goal is to teach how to apply these to Pinewood, then you explain balance point and moving it rearward for Kin En (change in drop height advantage).

You might even go so far as to point out all that Pot En changes to kinetic when the car is released?

I think the momentum demonstration and how it applies should be pretty clear: the heavier car doesn’t suffer much on the ramp due to the nature of acceleration yet it can keep going better on the flat.

My .02+

-Terry

[Go Bubba Go]

3) Do not constrain your car design to fit Pinewood derby rules...

Pot En -> just demonstrate different release heights, again free roll stops on flat to show difference… use same car, same mass...

TAL:

Teeeman "caught" me. I'm trying to encourage you to think outside the norm with regard to "rules", and I myself am "stuck" in thinking all the demos will have to occur with the cars being released from behind the pins.

Very good idea to demonstrate release from varying heights, especially a couple of low ones where the car doesn't even cross the finish line (provides that "wow, look at that..." that I mentioned above).

Good points, Terry.