whats more important amount of weight or com
- ohiofitter
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whats more important amount of weight or com
Lets say you have two cars, Both wedges same wheel base and all parts (wheels ,axle, and paint) weighed the same.
(Car 1) is 3/16 thick at front 1/4 inch thick at back, painted, wheels and axles weighs lets say 1 oz. 4 oz of weight put the com lets say 13/16 front of axle
(Car 2) is 3/16 thick at front 1/4 inch thick at back, painted, wheels and axles weighs lets say 2 oz. 3 oz of weight put the com lets say 13/16 front of axle
Now my question is seeing how both car are idenical in shape and the balance points is the same does one car have a advantage over the other and why
(Car 1) is 3/16 thick at front 1/4 inch thick at back, painted, wheels and axles weighs lets say 1 oz. 4 oz of weight put the com lets say 13/16 front of axle
(Car 2) is 3/16 thick at front 1/4 inch thick at back, painted, wheels and axles weighs lets say 2 oz. 3 oz of weight put the com lets say 13/16 front of axle
Now my question is seeing how both car are idenical in shape and the balance points is the same does one car have a advantage over the other and why
Re: whats more important amount of weight or com
Yes. Laws of Physics.
- Stan Pope
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Re: whats more important amount of weight or com
The difference in necessary ballast addition suggests that the wheels may be different, car 2 having heavier wheels than car 1. If this is true, then what probably happens?ohiofitter wrote:Lets say you have two cars, Both wedges same wheel base and all parts (wheels ,axle, and paint) weighed the same.
...
Now my question is seeing how both car are idenical in shape and the balance points is the same does one car have a advantage over the other and why
Stan
"If it's not for the boys, it's for the birds!"
"If it's not for the boys, it's for the birds!"
- FatSebastian
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Re: whats more important amount of weight or com
If the title of the topic is the question, the answer is that the placement of the CoM is more important than the amount of weight added to the body to reach 5 ounces, because the CoM placement determines the speed of the car in the flat. However, the ability to add more weight gives greater flexibility in positioning the CoM.ohiofitter wrote:what's more important amount of weight or com
Because OF says "all parts (wheels ,axle, and paint) weighed the same," I suspect the question may be an academic one supposing very dense wood v. very bulky wood. It may be another way of asking the weight placement question touched on in this recent topic and elsewhere.Stan Pope wrote:The difference in necessary ballast addition suggests that the wheels may be different, car 2 having heavier wheels than car 1.
- ohiofitter
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Re: whats more important amount of weight or com
Thank you fat , That what i was trying to find out in my senerio the denisty of the wood would have had to be different but regardless as long as the center of mass is at the let say 13/16 of an inch you could add as little as 1 oz and up to as much as 4 oz of addional weight
- Darin McGrew
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Re: whats more important amount of weight or com
So something like this?
Both cars are 3/16 thick at front, 1/4 inch thick at back, CM 13/16 in front of rear axle.
Car 1: 0.5oz wheels & axles, 0.5oz wood and 4oz ballast (lead, tungsten, whatever).
Car 2: 0.5oz wheels & axles, 1.5oz wood and 3oz ballast (lead, tungsten, whatever).
Is that about what you mean?
Both cars are 3/16 thick at front, 1/4 inch thick at back, CM 13/16 in front of rear axle.
Car 1: 0.5oz wheels & axles, 0.5oz wood and 4oz ballast (lead, tungsten, whatever).
Car 2: 0.5oz wheels & axles, 1.5oz wood and 3oz ballast (lead, tungsten, whatever).
Is that about what you mean?
- ohiofitter
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Re: whats more important amount of weight or com
Yeah darin, I meant if all the parts were identical to the t and the only thing different was the weight of the wood. Would 4 oz of ballast or 3 oz off ballast . Which car would be better. The ballast could be whatever you like to use for the senerio
- Darin McGrew
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Re: whats more important amount of weight or com
With more ballast and less wood, car 1 can have a lower rotational inertia because its mass can be more concentrated. Thus, car 1 loses less energy when it rotates. Cars rotate at the transition from the track's ramp to the track's level run (which gentle transitions will minimize). They rotate when the wheels hit a joint between sections or any other bump in the track surface (which smoother tracks will minimize). They rotate when they hit the guide rail and change course (which rail-riding will minimize).
It's a very minor effect, but all else being equal, car 1 will be slightly faster.
It's a very minor effect, but all else being equal, car 1 will be slightly faster.
- pwrd by tungsten
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Re: whats more important amount of weight or com
I also go for 3.6 ounces or more of tungsten. Sometimes up to 4.2 ounces. The more added weight the better...
W Racing!!!!