Recent content by Somes J

I'm trying to calculate skin friction drag on a truck so I can compare it to pressure drag. I can find the formula and typical coefficients for pressure drag easily enough but I've had a hard time finding it for skin friction. So far I've found this...

Probably a stupid question, but here goes: Horsepower always measures the amount of work an engine can perform in one minute and can be converted into watts by horsepower X 746 = engine power in watts, right? I ask this because I was wondering about something. According to...

I decided to try a different approach here. There are commercial cars that run on diesel, that should allow a more reliable car/truck comparison, as now I'm comparing the same type of engine, not converting between different engine types. The http://www.hybridcars.com/diesel-efficient-cars"...

Let me try rephrasing the OP a bit. In my calculation I got a result that a truck used less energy than a car pound for pound for a given mileage even assuming the engine efficiency was the same. This seemed puzzling to me because if anything I'd expect it to be the opposite (truck is less...

Something I was wondering about. I was doing some calculations on how much energy different types of vehicles consume, and I got a result that surprised me. For big trucks, I found an estimate of 5-6 MPG on the internet, divided the energy content of a gallon of diesel fuel by that, and then...

While bigger ships tend to be faster they are usually well below theoretical hull speed IIRC. http://www.globalsecurity.org/military/systems/ship/container-types.htm" http://www.sailingusa.info/cal__hull_speed.htm" gives hull speed of about 23 knots for a 100 meter hull, 33 knots for a 200...

Honestly my question was less motivated by curiosity about the specific issues with using nuclear power and more by curiosity about how the design of these big ships might be different in a world where fuel cost wasn't a serious issue. I read about some fast container ships that ran into...

I was doing some internet research on the idea of using nuclear reactors for cargo ships, and a couple of sites I found discussed the possibility of building fast cargo ships (> 30 knots) that would run on nuclear power so that they wouldn't face the economic difficulties with fuel price. E.g...

When ammonia dissolves in water some of it reacts to form ammonium and hydroxide ions: NH3 + H2O = NH4+ + OH- http://scifun.chem.wisc.edu/chemweek/pdf/ammonia.pdf" What happens if you then heat or boil the solution, driving off the ammonia? Does all the NH4+ turn back into NH3? Just...

Hi. I'm planning to use an all-ocean planet as a setting in a science fiction story, and I was wondering, what would the effect of an absence of continents be on the planet's weather? The planet is something like 98% water-covered, its only land is a number of islands, mostly small, the...

I thought perfectly circular orbits were basically impossible? Also Pluto and Charon are tidally locked to each other and http://ssd.jpl.nasa.gov/?sat_elem". Basically, I have the assumption based on my very limited knowledge that it's reasonable to think that the orbit of the two worlds around...

If the orbit was eccentric the tide would be stronger at perigee than at apogee, and the moon would move (slightly) back and forth in the sky as it pulled ahead of the planet's rotation at perigee and fell behind it at apogee. This is what I'm worried about in regards to whether the planet would...

Yes, I suppose I should have made reference to both worlds orbiting a common barycenter rather than a moon orbiting a planet.

Hello. I have a question concerning the stability of a hypothetical binary planet system. I'm sorry if this properly belongs in general astronomy instead of astrophysics, but it does concern orbital mechanics. The hypothetical system is an Earthlike planet orbiting a relatively bright K class...