A PWD riddle

[Guest]

Hey fellas,

I just thought I would try to get our minds off the race with a PWD riddle.

Is there enough room to fit weight in the rear of a 4oz rear weighted car to cause it to intentionally flip onto it's back, at the transition, and keep rolling to the finish? This is a plank car.

It would probably drop speed with the reversal of the dom, but imagine it was a circus event.

Would this be a way of getting around the "No moving weights" rule that is predominant in scout racing since the weight would kind of pendulum and actually be shifted to the front?

 

[W&K Creations]

A problem that I would think is that there is a rear clearance on the car where the back of the car can hit the track if its too low....Im not sure how far back the rear axel would need to be such that if you lifted the front of the car up and rotated back (around the rear axel as the fulcrum point) ....that the back of the car wouldnt hit the track and stop flipping over.

if the rear axel could be drilled far enough back to allow enough rear end clearance so it can flip over, my guess is that there would so little space in the back of the rear axel to put any weight, that effectively it wont have enough momentum to flip it over....

Now Im not a physics person at all and certainly the guys who have been racing here longer may have thought about this or perhaps seen it....but the videos that ive seen of cars flipping over is that yes they flip but they are doing so as part of the whole car flying off the track LOL....

 

[Minions Racing]

The wheels can not go past the end of the car body, so the back of the car would always hit the rail before it could flip over. If somehow you did get it to flip over, the new nose of your car is now 5 or 6 inches further away from the end of the track then it was before the flip.

 

[DerbyDad4Hire]

No way. Have to see it to believe it.

 

[GravityX]

No way. Have to see it to believe it.

Best response yet!

 

[bracketracer]

Hey fellas,

I just thought I would try to get our minds off the race with a PWD riddle.

Is there enough room to fit weight in the rear of a 4oz rear weighted car to cause it to intentionally flip onto it's back, at the transition, and keep rolling to the finish? This is a plank car.

It would probably drop speed with the reversal of the dom, but imagine it was a circus event.

Would this be a way of getting around the "No moving weights" rule that is predominant in scout racing since the weight would kind of pendulum and actually be shifted to the front?

laserman, what you need to do is figure out a way to make the car flip FORWARD! That way, it would shorten the distance to the finish line! You could name it "The Slinky". Start with a car heavily weighted in the nose so you get the quick launch, then WHAM! It flips forward, putting the COM in the rear so you get the big speed down the hill AND you're about seven inches closer to the finish line. Now you just need to figure out what makes the WHAM! work?

 

[down4derby]

Fill the rear wheels with weight , shorten and trim the rear of the body just enough to clear the inside of the rail and load the rest of the weight behind and above the rear axle line. Then creat a severe uprake towards the front under the body so air pressure helps push it over. Might work. Would be fun to watch.

 

[zeebzob]

The only way I could picture this is to shorten the car and have like 4 inch diameter wheels with all the weight behind the axle.

 

[Quicktimederby]

So much for rail running!!

 

[Guest]

Fill the rear wheels with weight , shorten and trim the rear of the body just enough to clear the inside of the rail and load the rest of the weight behind and above the rear axle line. Then creat a severe uprake towards the front under the body so air pressure helps push it over. Might work. Would be fun to watch.

Hey Down 4 Derby,

This answer was closest to what I was thinking when I posed the riddle. I guess you win the steak knives. Of course Zeeb also pointed out that certain specifications were not mentioned such as the diameter of the rear wheels. The type of weight to be used was also omitted etc. but this riddle was not about semantics.

The way I figure it there is a radius of about .275 behind the rear axle that can be weighted, and the car can go no further back than that as well. This should be just enough room for 3 rows of 1/4" cubes to be placed almost directly above, beneath, and behind the axle (3oz). If a person were to use 7 cubes in each row instead of the normal 6 this brings the total to about 3.5oz. Plus the space between the cubes that trace the .275 radius can be filled.
However there is still some room to put some more weight. As D4D pointed out there is space within the wheel cavity. Perhaps enough for an extra 1/4oz or more without making contact with the wheel.

Not sure if this is what you meant by filling the wheel but the alternative way of reading the sentence might also work.
(By filling the wheel with weight ( heavy wheel) it would conform to the wording of the riddle while effectively taking that portion of the weight out of the equation.)

There is still more room though. The space between the wheel and the guide rail can be used during the flip. This would allow a person the have a semi circular weight, almost the same diameter as the wheels probably about .06" thick. This would probably necessitate the rear wheels to not be canted to allow for a little extra space, but would most likely put 4oz of weight within an area that would still give clearance for the flip.

Hey Bracket,
Just wait for the day my car does a Smokey and the Bandit style flying barrel roll over two lanes of traffic and land directly in front of your car.

 

[Mr Chips Racing]

Where is Murph when we need him?

 

[Guest]

Where is Murph when we need him?

LOL. Sorry Mr. Chips.

I can't help but be myself, even if I do talk too much.

Wish you could be there at the race but it sounds like you are busy with slightly more important things like earning a living while the iron is hot.

Best,

 

[Rocket car]

I did build a wheelie car once for the boy scouts. It had 6 wheels on it and was V shaped from the side view. The balance point was at the middle wheels. It popped a wheelie at the bottom of the hill and held it to the finish line. All the kids loved it!!!

 

[Guest]

Hey Rocket Car,

That is awesome!!!

Do you have a photo of it?

I figure that this is a way of actually GAINING a some length to your car.
Not that it would translate to speed, but still an interesting fact.

I am most curious about what happens when it tips.

Does it slow down or speed up?
At what part of the bottom does it tip?

Thanks,

 

[bracketracer]

Hey Bracket,
Just wait for the day my car does a Smokey and the Bandit style flying barrel roll over two lanes of traffic and land directly in front of your car.

Pfft! like you could get in front of me! j/k!

I want to see you do a Hooper style jump though, less the rocket!
https://www.youtube.com/watch?v=q0Y3A-zib-Q

 

[Guest]

Hey Bracket,
Just wait for the day my car does a Smokey and the Bandit style flying barrel roll over two lanes of traffic and land directly in front of your car.

Pfft! like you could get in front of me! j/k!

Well, I guess that is one glaring flaw in the plan.

You never know though. Perhaps the mailman gets attacked by a sasquatch type creature and upon barely escaping with his life he manages to pry loose, from the yeti type beast, your car from it's jaws. This would be a very plausible scenario on how my car can get the lead on you.

 

[bracketracer]

Well, I guess that is one glaring flaw in the plan.

You never know though. Perhaps the mailman gets attacked by a sasquatch type creature and upon barely escaping with his life he manages to pry loose, from the yeti type beast, your car from it's jaws. This would be a very plausible scenario on how my car can get the lead on you.

True, except I ship with UPS not the USPS. Squatches won't go near a brown truck. You probably didn't know that, living in the city and all.

 

[Rocket car]

Hey Rocket Car,

That is awesome!!!

Do you have a photo of it?

I figure that this is a way of actually GAINING a some length to your car.
Not that it would translate to speed, but still an interesting fact.

I am most curious about what happens when it tips.

Does it slow down or speed up?
At what part of the bottom does it tip?

Thanks,

No pictures. Popped a wheelie on the flat part. The car slowed down but still made it across the finish line. I should say that it was more like a boomerang shape more than a V.

 

[Guest]

Well, I guess that is one glaring flaw in the plan.

You never know though. Perhaps the mailman gets attacked by a sasquatch type creature and upon barely escaping with his life he manages to pry loose, from the yeti type beast, your car from it's jaws. This would be a very plausible scenario on how my car can get the lead on you.

True, except I ship with UPS not the USPS. Squatches won't go near a brown truck. You probably didn't know that, living in the city and all.

HAHAHAH.LOL

That movie "Hooper was awesome" I have not seen it in a while but the opening where he drives backwards on the highway was hilarious!

PS. We have city Squatches. They are disguised as trash and also attack only USPS!

Rocket Car,
That sounds like a cool little machine you made.