# Search results

1. ### Light and PV solar panels

Hi, I am wondering if all the different wavelengths (ie colors) of light are absorbed by a PV panel, and if so is the absorption equal among all the wavelengths? Is there any wavelength(s) that are more readily reflected off the glass or the PV cell itself? Thanks a lot! Scott
2. ### Question about horsepower for car

Thanks for the info! Is it at all possible to get a ballpark number for horsepower based on the parameters I have given. If so, a thousand thanks!
3. ### Question about horsepower for car

I am wondering how much horsepower would be needed, or generated (not sure which term is right), if a diesel car with a 250HP motor, and weighs 3,500 pounds, is going up a slight incline (maybe 2 or 3 degrees) averaging 20 mph? Thanks.
4. ### Electric vehicles vs gasoline vehicles

Will an electric vehicle use less joules going up a hill than a gasoline vehicle, because electric vehicles are more efficient? I've read that electric vehicles use on average 800,000 joules per mile, while gas vehicles use 3.3 million joules per mile. Assuming those numbers are based on...
5. ### Can this method turn potential energy into kinetic energy?

Thanks for the tip about the difference between power and energy. I'm wondering if its correct, mathematically and the correct terminology, to say that the scenario I described constitutes a 24.5KW power plant, if only for 60 seconds?
6. ### Can this method turn potential energy into kinetic energy?

I am wondering if this method is in use already somewhere, or if its possible to be used. For example, using the equation of gravitational potential energy a 100kg weight that freefalls 100 meters has 98,000 J of energy, which equals 24,000 watts after approx 4 seconds of freefall. Assuming I...
7. ### Info on tests done in the past for expanding universe

I am hoping that someone with broad knowledge of the physics literature can tell me when in the past tests were done on light coming from galaxies billions of light years away, tests that over time counted a decreasing number of photons from a single galaxy, or an increase in the wavelength of...
8. ### Question about gravitational potential energy

I am wondering how this all works and am hoping to get some guidance. If a 1000 lb weight freefalls vertically from 660 ft the energy is 894,289 joules. If the fall is down a 30 degree slope that is 1300 ft long, then it takes 17 seconds and the potential energy can be said to be 53 KW. If...
9. ### Why the discrepancy between telescopes and big bang?

I appreciate all the answers but I still don't understand how the BB explains that the HST imaged the oldest galaxies ever seen and they were 13-plus billion light years away, 13-plus billion years ago which is right around the time the theory says the bang happened. I am pretty certain the...
10. ### Why the discrepancy between telescopes and big bang?

I can't get enough of those HST images with all the galaxies, but is the telescope telling us that 13.7 billion years ago those galaxies were 13.7 billion light years away and in every direction, rather than clumped together as the theory says. How does Big Bang theory account for that?
11. ### Why the discrepancy between telescopes and big bang?

I am wondering why it is that we can look into Hubble's Deep Field and see galaxies 13.7 billion light years away, and 13.7 billion years ago, yet Big Bang theory tells us that 13.7 billion years ago all matter in the universe was very close together. Shouldn't we be seeing in HST that the...
12. ### Generating electricity

The equation for gravitational potential energy gives a higher number of KW's the less time it takes a weight to descend, but it seems like the more time a weight spends descending the higher the KW number would be because the rotor would have a higher resistance for a longer time. Am I missing...
13. ### Generating electricity

Thanks for the chuckle! The weight coming down to generate electricity is in the realm of physics, but getting that weight back up to the top also has a lot to do with economics. A simple, sustainable and profitable method will generate electricity for much longer than the pyramids have stood...
14. ### Generating electricity

So if the descent takes 4 minutes, then 10.2 million joules of energy divided by 240 seconds equals 42,500 watts of power? Thanks a ton (in this case 5 tons) for all the advice!
15. ### Generating electricity

Thanks for the advice about grav potential energy! The equation gave me an answer of 10.2 million joules. I took that to mean the system would produce 10.2 million watts every second, but since it's on a 30 degree incline rather than 90 degrees, only 1/3, or 3.4 million watts, would be...
16. ### Generating electricity

What possible rate of electricity would be generated if a 10,000 lb weight goes down a 30 degree inclined track, attached by a cable that spins the rotor in a generator mounted at the top of the track? Please assume that friction on the track is minimal and that there is a large supply of these...