Hovercraft B/C

[Tesel]

To add to that, weight scores are much more consistent than time scores. Once you get to the point where you have a powerful hovercraft, you can guarantee the weight score is successful. Time score is less consistent; obviously, it is important, but not as important as being able to handle all 16 rolls of pennies.

I wouldnt say it is "not as important as being able to handle all 16 rolls of pennies", far from it. Science Olympiad is all about relative performance: you don't have to be good, just better than everyone else. If your tournament is riddled with foam tray crafts, then mass score becomes more important. If however, when your team goes to the regional, state and possibly national level, all teams will have mastered the mass score, and time scoring becomes the critical deciding factor. To handle this additional 2kg, I would highly encourage you all to build your craft out of wood: while it is a time investment, it is much less likely to variation and fragility. It isn't a good mass score that makes your proctor gawk, its the accuracy to which you can predict your time. Any Neanderthal can over-engineer a craft to carry 2kg and consistently reach inaccurate times.

Of course you have to get both to be competitive, and I never said anything to the contrary. However, mass score is a lot more predictable than time score, so it is a better idea to get the mass score reliable first, and then focus on adjusting timing.

[starfruit]

Does anyone know any good resources/tips for learning physics? That's the part of the event where I usually have the most trouble.

[shrewdPanther46]

By event design, they tried to simplify it to make it easy to study. My suggestion is to first watch videos or something to understand the basis of the concepts, and then buy a textbook and read through it. The most important thing is practice, and that applies to all levels of physics all the way up to physics olympiad

[MattChina]

By event design, they tried to simplify it to make it easy to study. My suggestion is to first watch videos or something to understand the basis of the concepts, and then buy a textbook and read through it. The most important thing is practice, and that applies to all levels of physics all the way up to physics olympiad

I agree. The best way to learn physics is step by step. First, understand the basics and get acquainted with all the equations. Then once you are familiar with the topics practice as much as possible by doing practice problems and finding tests online.

[rc2000]

I know that you need a high static pressure for lift fans, but does cfm matter for list as well? for example, i found this one that i might use https://www.digikey.com/product-detail/ ... ND/5230580 is that a good choice for lift? (max load)

I just purchased that fan actually. I have yet to assemble it on to my hovercraft, but it is very strong, rivaling DC motors.

[geniusjohn5]

Has anyone tested the effectiveness of 1600 mah vs. 3000 mah battery? Are the differences between discharging at a rate of 1600 miliamps in 1 hour vs. 3000 milliamps in 1 hr small or large, given the relative short time constraints of the event? I would assume that the fact that I am only allowed 5 failed or 2 successful(at most 45 secs per run) runs would imply that the total time I run/test the hovercraft is pretty short. Because of the short amount of time allotted, I think there's a very small difference between the 1600 mah and 3000 mah battery. Can anyone please confirm? If you could explain in more detail and more clearly, that would be better.

[Tesel]

Has anyone tested the effectiveness of 1600 mah vs. 3000 mah battery? Are the differences between discharging at a rate of 1600 miliamps in 1 hour vs. 3000 milliamps in 1 hr small or large, given the relative short time constraints of the event? I would assume that the fact that I am only allowed 5 failed or 2 successful(at most 45 secs per run) runs would imply that the total time I run/test the hovercraft is pretty short. Because of the short amount of time allotted, I think there's a very small difference between the 1600 mah and 3000 mah battery. Can anyone please confirm? If you could explain in more detail and more clearly, that would be better.

To be truthful, we actually encounter some voltage drop during the event with 3000 mAh batteries. The time is short, but especially if you're using commercial fans, the equipment draws a lot of power.

[geniusjohn5]

Has anyone tested the effectiveness of 1600 mah vs. 3000 mah battery? Are the differences between discharging at a rate of 1600 miliamps in 1 hour vs. 3000 milliamps in 1 hr small or large, given the relative short time constraints of the event? I would assume that the fact that I am only allowed 5 failed or 2 successful(at most 45 secs per run) runs would imply that the total time I run/test the hovercraft is pretty short. Because of the short amount of time allotted, I think there's a very small difference between the 1600 mah and 3000 mah battery. Can anyone please confirm? If you could explain in more detail and more clearly, that would be better.

To be truthful, we actually encounter some voltage drop during the event with 3000 mAh batteries. The time is short, but especially if you're using commercial fans, the equipment draws a lot of power.

So are you basically saying that even 8.4 v NiMH3000 mAh batteries may not even be enough to run a successful hovercraft? (BTW, sorry for all these questions, I can't "experiment" with different materials because once I buy something online using the school's money, I can't sell it back/reimburse it.)

[Adi1008]

Has anyone tested the effectiveness of 1600 mah vs. 3000 mah battery? Are the differences between discharging at a rate of 1600 miliamps in 1 hour vs. 3000 milliamps in 1 hr small or large, given the relative short time constraints of the event? I would assume that the fact that I am only allowed 5 failed or 2 successful(at most 45 secs per run) runs would imply that the total time I run/test the hovercraft is pretty short. Because of the short amount of time allotted, I think there's a very small difference between the 1600 mah and 3000 mah battery. Can anyone please confirm? If you could explain in more detail and more clearly, that would be better.

To be truthful, we actually encounter some voltage drop during the event with 3000 mAh batteries. The time is short, but especially if you're using commercial fans, the equipment draws a lot of power.

So are you basically saying that even 8.4 v NiMH3000 mAh batteries may not even be enough to run a successful hovercraft? (BTW, sorry for all these questions, I can't "experiment" with different materials because once I buy something online using the school's money, I can't sell it back/reimburse it.)

I've seen devices using batteries like that which are pretty successful. A little voltage drop is okay as long as you're able to get some successful runs in.

[Tesel]

To be truthful, we actually encounter some voltage drop during the event with 3000 mAh batteries. The time is short, but especially if you're using commercial fans, the equipment draws a lot of power.

So are you basically saying that even 8.4 v NiMH3000 mAh batteries may not even be enough to run a successful hovercraft? (BTW, sorry for all these questions, I can't "experiment" with different materials because once I buy something online using the school's money, I can't sell it back/reimburse it.)

I've seen devices using batteries like that which are pretty successful. A little voltage drop is okay as long as you're able to get some successful runs in.

Yeah don't get me wrong, they work perfectly fine, but even at 3000 mAh, you can tell the batteries have limitations. I wouldn't go any lower.