Mission Possible C

[twototwenty]

Frankly, I think the entire black box "rule" is extremely subjective/should be taken on a case by case basis. Take for the example turning on a light bulb. While that is a clear conversion of electricity to light (a good scientist would recognize the chemical part of that too, of course), according to the black box rule, that is no conversion you should get points for. Thus, unless you are making your own light bulbs or LEDs (which most teams do not have the capacity to do, obviously), I can see no way one would convert electricity to light.

Furthermore, as I read them, the rules specifically allow for the use of batteries as energy conversion mechanisms, as per rule 3e. By my personal interpretation (although, of course, I am not an event supervisor), that would include the fact that they convert chemical energy to electricity.

That being said, I do think that some judgements of whether something is a scorable energy transfer or not is going to vary with the event supervisor. Hopefully, there will be a rule clarification or two about it.

Also, a quick question of my own: do you all think using a mechanical force to close a switch would actually be a mechanical-to-electrical conversion? Because the energy for the electricity is still coming from the battery, not the switch being closed.

[olympiaddict]

Gorf250 summed up basically what I was wondering after thinking about it since those posts. Maybe one of the rules writers could weigh in to give us a little better understanding? I'm pretty unsure.

[iwonder]

Also, a quick question of my own: do you all think using a mechanical force to close a switch would actually be a mechanical-to-electrical conversion? Because the energy for the electricity is still coming from the battery, not the switch being closed.

Personally, I think it would have to count. If not, then all the energy ever used in the device would come from whatever the first transfer started with. In this case dropping an assortment of items in the device, and that's not much energy considering all the losses in these transfers. Then again, it's possible that the transfer you talk about doesn't count, but an electrical->thermal transfer would count using battery energy... I hate to sound like a broken record but it should probably be added to a clarifications list with the other half a billion questions

[gorf250]

This whole theoretical "blackbox" rule is still perplexing. For example, assume a lightbulb wouldn't count as electrical to ems, but would a just running current through a nichrome wire count? It's not like one requires more effort by the competitor, and each pretty much completes the transfer on its own. If a candle doesn't count as chemical to thermal, does a purchased string coated in wax count? What about just a string, or even a piece of wood? These would all produce the same result (heat), with very little effort by the student, so could any of these recieve points according to this "blackbox" rule?

[chalker]

Also, a quick question of my own: do you all think using a mechanical force to close a switch would actually be a mechanical-to-electrical conversion? Because the energy for the electricity is still coming from the battery, not the switch being closed.

here's something that might help you think about this better: 4.b says "directly transfers from one basic energy form to another".

First think about a wire hooked to a motor that's hooked to a switch connected to 2 wires. In this case you transfer electrical energy to mechanical via the motor, then use the mechanical energy on the switch to permit the passage of electricity.

Compare that to a wire hooked to a light bulb that's aimed at a photocell that's connected to 2 wires. In this case you transfer electrical energy to EM energy, then use the EM energy on the photocell to permit the passage of electricity. A photocell is essentially a switch (e.g. it doesn't have to be a 'solar' cell that outputs energy, but can be a 'phototransistor' type).

Is there any fundamental difference between the 2 situations? I don't believe there is. Of course this isn't the place for official clarifications as always....

[chalker]

As I typically do at the beginning of the season, I thought I'd post a brief analysis of what might be the max possible score. Assume this is Nationals and 120s is picked as the ideal time (which you hit exactly), and you do the starting, bonus and final tasks, along with another 15 energy transfers to get max points. Doing a total of 18 tasks is going to take quite a bit of space. Let's assume you get the box down to 30 cm per side (which is pretty small for that amount of tasks).

4.a.: 100 pts
4.g.: 250 pts
5.c.: 30 + 30 + 30 = 90 pts
5.d.: 240 pts
5.e.: 150 pts
5.f.: 25 pts
5.g.: 25 pts
5.h.: 25 pts
5.i.: 25 pts
5.j.: 50 pts
5.k.: 150 pts
5.l.: 100 pts
5.m.: 50 pts

Total= 1280 pts

Note that there is a bit of a tradeoff to be made between adding tasks and taking up more space. It's impossible to come up with a precise calculation for this, but a rough rule of thumb is as follows:

1 cubic cm of space saved = 3 points
First instance of each energy form = 30 pts = 10 cubic cm
Second instance of each energy form = 20 pts = ~7 cubic cm
Third instance of each energy form = 10 pts = ~3 cubic cm

[olympiaddict]

It's also good to keep in mind that if you already have a box of a given size- say 30x30x30, if you add more space, say 3 cm out one side, you gain 30x30x3 cubic centimeters, but only sacrifice 3 points.

Thanks for the tally! Super helpful

[SciJ]

Personally, I think it would have to count. If not, then all the energy ever used in the device would come from whatever the first transfer started with. In this case dropping an assortment of items in the device, and that's not much energy considering all the losses in these transfers. Then again, it's possible that the transfer you talk about doesn't count, but an electrical->thermal transfer would count using battery energy... I hate to sound like a broken record but it should probably be added to a clarifications list with the other half a billion questions

Couldn't you just have energy transfers that trigger other energy transfers? e.g. convert A to B, B hits a switch, allowing C to convert to D?

[iwonder]

Yeah, that's the second part of my post... I kinda realized halfway through writing it that that was possible

It's been a long week and it's only wednesday....

[gorf250]

Couldn't you just have energy transfers that trigger other energy transfers? e.g. convert A to B, B hits a switch, allowing C to convert to D?

This is my interpretations of the rules, a series of energy CONVERSIONS that trigger the next conversion. I personally wouldn't see flipping a switch as the device transferring mechanical energy to electrical energy. However, this would make some transfers nearly impossible. Ex. transferring mechanical energy to ems.