Mission Possible C

[olympiaddict]

does anyone have any good sources for legal components that are classified as photodiodes or phototransistors?
Also, I'm a bit unsure how one would use one of these devices effectively. I suppose one would be able to buy different sensitivity components that trigger at different light levels, but I'm not sure how I'd figure out what I need beforehand. My first thought was to just go the voltage divider with photoresistor route, but regular resistors are not legal components
Can anyone give me some advice or links about this

[Scioly4Fun]

Does a battery count as both a chemical reaction and a transfer producing electricity, or is it just a source of electricity? For example, would closing a switch that activates a circuit with a battery count as mechanical -> chemical (in battery) -> electrical, or simply mechanical -> electrical?

Also does a candle count automatically as both a chemical reaction and a transfer of heat (thermal energy) /or light (electromagnetic energy)? For example if an igniter lights a candle could this be counted as electrical -> heat (from igniter) -> chemical reaction -> heat/or light (from candle)?

[Flavorflav]

Does a battery count as both a chemical reaction and a transfer producing electricity, or is it just a source of electricity? For example, would closing a switch that activates a circuit with a battery count as mechanical -> chemical (in battery) -> electrical, or simply mechanical -> electrical?

Also does a candle count automatically as both a chemical reaction and a transfer of heat (thermal energy) /or light (electromagnetic energy)? For example if an igniter lights a candle could this be counted as electrical -> heat (from igniter) -> chemical reaction -> heat/or light (from candle)?

This was discussed on the first page of the thread. There is some debate, but in general you will not be allowed to count any energy that you neither stored nor directly harnessed. In the case of the battery, unless you built it yourself you did not cause the chemical reaction to occur and did not directly harness chemical energy, so you do not score that transfer. You do score the electrical energy, because you are directly harnessing that with your next action, so you would only score mechanical to electrical. The candle is a parallel case - in your example, you could only score electrical --> thermal --> EMS. At least that is my understanding.

[olympiaddict]

I'm not convinced you wouldn't score for the battery just because it was a commercially made battery. First of all, the rules seem to prohibit homemade batteries by saying all batteries must be factory sealed and voltage labeled by the manufacturer. At the same time, the rules specify that batteries may score points depending on how they are used, and they say this in conjunction with mentioning that rocket igniters and candles can score points. These are all energy-conversion devices, so I don't think it's referring to the electricity created by the battery scoring points. Taking all this into account I don't think the rules prohibit these kind of devices from scoring points just because they are not homemade.

[twototwenty]

I'm not convinced you wouldn't score for the battery just because it was a commercially made battery. First of all, the rules seem to prohibit homemade batteries by saying all batteries must be factory sealed and voltage labeled by the manufacturer. At the same time, the rules specify that batteries may score points depending on how they are used, and they say this in conjunction with mentioning that rocket igniters and candles can score points. These are all energy-conversion devices, so I don't think it's referring to the electricity created by the battery scoring points. Taking all this into account I don't think the rules prohibit these kind of devices from scoring points just because they are not homemade.

You bring up a good point...any non-"black box" chemical to electrical conversion would have a high risk of being considered a home-made battery. Personally, I think the much safer route (barring any rule clarifications on the topic) as far as not risking loss of points would be to consider the activation of a battery a viable chemical to electrical conversion.

[Flavorflav]

But since all your electricity is coming from batteries and because you have to activate it by means of a some kind of switch, your theory would imply that every use of electricity is actually mechanical-chemical-electrical. I don't buy it, and I'm not going to score it that way unless I see something pretty clear from one of the Big Cheeses who hang around here.

Olympiadaddict, which region are you in? If no clarification is forthcoming soon, you might want to get a ruling about this from whoever will be running the event at your regionals before you design around it. If they don't buy it either, you'd lose not only the points for the transfer, but also for the accurate TSL.

The language about factory-sealed batteries is stock and has been used in many events. I would be interested to hear from someone on the committee if they intended to rule out homemade batteries.

[olympiaddict]

whose theory was the first paragraph referring to?

True. I submitted a State clarification, so that would apply at regionals.

that's true, but given the way the rules are written, unless there's a clarification that alters those rules, in my opinion the only way to transfer chemical to electrical is with a commercial battery.

[Flavorflav]

Let's throw it up to experienced event supervisors on here: If a device closed a switch which allowed current to flow from a battery and the current caused the next action, would you allow that to score as mechanical-> chemical and chemical -> electrical, or simply as mechanical -> electrical?

[penclspinner]

Let's throw it up to experienced event supervisors on here: If a device closed a switch which allowed current to flow from a battery and the current caused the next action, would you allow that to score as mechanical-> chemical and chemical -> electrical, or simply as mechanical -> electrical?

I'd score it as mechanical -> electrical

[Balsa Man]

For what it's worth, back in 2005, the last time MP used scoring for transfers of the various forms of energy, a switch allowing current flow from a (commercial) battery was mechanical to electrical. Homemade battery (allowed, and as I recall, counting for a bonus) counted as chemical to electrical.