It's Harder To Get an Uber or Lyft If You're Black, Study Says (time.com) 476
Comment Re:What device can use 1Tb? (Score 1) 98
all porn that can be invented has been invented
Charles H. Duell
Comment Re:I can't not read that as "Baby Kale" (Score 1) 234
The letters qu put together have a sound. That sound is not the K sound.
This is my excuse for being late when I was unable to able to find the Queens Key address I'd been given on the phone at 8AM. Nothing to do with me being a simple moron at that time of the day.
Comment Re: This is a great loss (Score 1) 160
Clearly it should be renamed to 'Deb'
show some respect for his contribution
Comment Re:Not twice as safe I feel (Score 1) 379
Comment Re:Basic arithmetics of good (Score 1) 653
Comment Re:Easter liability (Score 2) 290
Comment Re:This guy has a better idea (Score 1) 221
Comment Re:Please be an Onion link please be an Onion link (Score 1) 221
Looking at the fueleconomy.gov link and only considering the useful output power which is what I was really imagining above; probably less than 55hp for the typical car at cruise and ~22kW for the Tesla. Then while maintaining a cruise the useful power is only split between:
- Rolling Resistance = 7-11%
- Air resistance = 11-16%
Depending on speed either drag or rolling resistance are going to dominate the power required. I really had never considered rolling resistance to be of great importance to a car despite my experiences on a bicycle.
Comment Re:Please be an Onion link please be an Onion link (Score 1) 221
I've got an EcoBoost Fiesta and during the winter here (Canada) the pressure gauges on most of the air pumps at the gas stations seize in the cold and so are practically useless. When it was finally warm enough to accurately check the pressure in my tires they were all around 30-32psi. After inflating them back to the recommended 38psi I noticed my economy improved from 6.5 l/100km to 5.5 l/100km although admittedly the average temperatures had also warmed up from around -15 to -5C. Even so it was enough of an improvement that I was surprised and will be checking tire pressures more frequently in future.
Comment Re:Please be an Onion link please be an Onion link (Score 1) 221
At 60mph the air resistance will be about 85N or about 2.3kW. This is far less than I would have thought and appears much less significant than the typical rolling resistance.
Comment Re:Please be an Onion link please be an Onion link (Score 1) 221
441N x 26.8 m/s = 11.8 kW
Using wikipedia figures the Tesla seems to require approximately 22kW at 60mph but it is extremely low drag and probably has lower rolling resistance than the typical value above. However I'd bet most cars are using 40kW (~55hp) or less to cruise at 60 resulting in the rolling resistance being responsible for 25-50% of the power requirements. I'm not convinced it would be worth it in many cases but recovering 10% of the energy could provide 1kW, the same as a 70A alternator.