Let's Make Robots!

Impossible Question...

I was driving with my son Phoenix, in the truck when he asked about the things hanging from my rear-view mirror and why they swing during corners. I explained centrifugal force, which he easily understood. The very next day as I was adding wood to the fire, he asked, "if there was a fire in your truck, would the flames bend when you turned"? First off, I was amazed and proud at what a kick-ass question this was coming from a 6-year-old. Second, I was struck with the fact that I had no friggin' idea. So, here is the question, fellow geeks and nerds...

(all of this assumes you can remove the wind factor)

A) Does a flame have mass?


B)  Is a flame affected by centrifugal force?

Now, tell me that is not a damn-good question.

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personally i think the flame would be affected, a flame, has a mass that is why it is affected by gravety and why it takes a tear drop shape,sort off, I know that in weightlessnes the flame has a ball like shape so it is posible to asume that it would be affected. I do see a problem with trying it in a car, whenver you turn, speed up, brake or anything elts that affects the speed and direction of the car the air inside the car moves, so that could affect the experiment.

Don't light up your car. Light up your robot! Walter seems to have all the right qualities!

About candle flames:

I happen to know (although sadly not from personal observation) that a candle will not burn in micro gravity. That means: you need gravity to keep a flame going. My point is: a flame is more than just a mass of gass. It is the visible (audible, tangible) manifestation of a physical process. It is a phenomenom.

The gravity needs to be there, so that the lighter gases (flame, exhaust) can travel away from the process (upwards), while the heavier gases (air = oxygen among other gases) can travel towards the process.

The real point here is: if you focus on just the visible part of this system, you will neglect to account for all the other stuff going on. That's why you cannot isolate your experiment in a glass cube. Your flame would suffocate. Phoenix would probably be interested in that "failure" as well.

If you would create some glass cylinder around the flame (to protect it from wind) you effectively create a funnel, a furnace. Compare the storm lamp. And if you would create some sort of burner strong enough to overcome any wind, you would probably bias the experiment with the strong upwards flow of a fuel/air mixture.

I have no idea how to introduce these complications directly into the mental model of the physical world inside a 6 year old brain (or a 6 year old's brain). And I think it is none of our business as parents/educators. As a parent, Chris, you should continue to be the proudest dad in the world. And let your son feel that. As an educator you should encourage him to strap a candle onto his rolling toys and (under supervision of the resident Safety Officer / Gushing Dad / Camera Man) light it up. And then drive it around. And observe.

Don't forget to make him evaluate the experiment. Preferably on video for our sakes. But judging from the delayed question (from car experience to fireplace experience), that could take the better part of a week.

As It Should.

8ik (burned a few eyebrows in his day)

You nailed it, girl!!

I think I have asked 50 people this question... You are the first! 


Looks like this has been thought about before....

for spolers click here.

wow, interesting that the enclosure makes the difference here. i'd never said it

perfect, this will be discussed at the breakfast round table tomorrow! Dim sum and physics!!!


Keep this conversation going, please! There is allready a light split going on what we think would happen. Well, if a group of robot-geeks are devided on a phyisics question, it's gotta be a damn good question!

Seriously, I know, I know, everyone thinks their kid is the greatest/ cutest/ smartest/ whatever...But man, my kid asked a question that stumped Robot-Geeks!!!


Flames are gasses and gasses do have mass. So flames would be affected by centrifugal force.
Maybe a few impossible answers.
I see Zanthess agrees with me about opposite direction and video. I think you should try this.