Recent content by petitericeball

Hello everybody, I'm working on a project and I want to verify a few theories I have. I'm unfamiliar with equipment for taking these types of measurements, so I wanted a little bit of help on this. Basically a bb is fired from an airsoft gun (350-550 fps), and I want to find the...

After looking around, I think I found some for around $30...

Hey guys, I'm looking for some sort of mosfet/relay/switch that can handle up to 1 milliamp and 8kV. I don't understand the technology very well, but from talking to some people, I know I can put 2 4kV mosfets in series to achieve my 8kV goal. On the other hand, while looking for relays, I...

Hey, I was doing some problems involving finding the moment of inertia of a spun spandrel, and I came across the idea of using the centroid to find the moment. For example, if you have a parabola, find the centroid. If you're rotating around the x-axis (y=x^2), then find y_bar and multiply...

So I posted this in the Electrical Engineering forum, and with 41 views and no replies, it appears I put it in the wrong forum, so here we go... Hi, I'm currently working on a project and I was wondering whether you guys were familiar with these "devices". SMA's are shape memory alloys, and...

I was about to recommend a faraday cage myself..

Hi, I'm currently working on a project and I was wondering whether you guys were familiar with these "devices". SMA's are shape memory alloys, and TEC's are thermoelectric coolers/peltiers. I tried looking for a pretty long time to find the specs on shape memory alloy (more specifically NiTiNOL)...

Thanks for the quick reply The closest thing I have to testing CO2 levels is a pH indicator (bromothymol blue I think) and a 4dKH reference solution, so when the solution is green, then the CO2 levels are between 20-40ppm I think. As for degassing, I guess it would be pretty hard to...

So, I'm making a non-yeast based CO2 reactor for my fish tank, and currently the idea has come down to baking soda, an acid, and a iv drip line to control the rate of the reaction. My first question, is what is the best acid to use that will produce stable, non harmful salts as byproducts...

Okay, I'll go through what I actually need to do... I am using a venturi (mazzei injector) to pump CO2 into my fish tank for the plants (I know.. nerdy) and am also supplementing macro/micronutrients. For the venturi to work properly, it needs between 5-10 psi of pressure (when the venturi goes...

I'm starting a project involving a venturi and water, and for the venturi, I need the water pressure to be around 7-10 psi. This means for my water pump, the head height must be around 15-20 ft. Most pumps that fulfill this requirement are either too expensive or are too powerful for my...

Okay thanks a bunch. :)

So, according to a site I found, the moment of inertia of a disk with the center cut out will be \frac{1}{2}M(r^2+R^2) so I'll post the revised results here along with the corrections from earlier. So, T-\vec {F}_{friction} = m \vec{a} (This T is force) \Sigma T =...

Thanks for the reply. Yes I did write the equations with respect to the center of mass, but didn't realize my mistake. So if I change the - to a + sign, then the rest is correct? \Sigma T = Tr + F_{friction}R So I'm going to edit the original post to...

Homework Statement A spool rests on a horizontal surface on which it rolls without slipping. The middle section of the spool has a radius r and is very light compared with the ends of the cylinder which have radius R and together have mass M. A string is wrapped around the middle section so...