For a race car you could use ultracapacitors instead of batteries. How much current can your charge cable handle...?
Not realistic with current capacitor tech. At best, caps can currently store about 1/5th of the capacity of a battery of similar mass. The best production ultracaps are around 30Wh/kg, whereas LiPo batteries are well over 100Wh/kg, and can exceed 200Wh/kg for certain variants.
Well, it's not efficiency for starters, it's efficacy. And "output"/"input" is all a matter of perspective: I don't put a fixed amount of fuel in my car and then want to know how far I can drive. I know how far I must drive, so L/100km gives me consumption and therefore fuel cost of my commute. Hence I can readily estimate weekly, monthly, or yearly fuel cost.
It's also linear: 12L/100km is 20% worse than 10L/100km, and 8L/100km is 20% better, for a known distance that needs to be travelled. 8.33km/L -> 10km/L -> 12.5km/L is not linear. Whether you prefer a linear-proportional scale or inversely-proportional scale in this matter is up to you.
Consider that distance travelled is fixed (it is for me) and therefore distance is the "input", and fuel consumption (or cost) is the "output" - albeit a negative output - and then it makes perfect sense.
of course I didn't believe that it took photos, but to imply that 3d stereoscopic photography is rare is simply untrue, considering 1.5 billion viewmaster disks have been produced.
Immaculate conception doesn't refer to the virgin birth (of Christ) but rather the doctrine that Mary herself was born immaculate (free from original sin), which has no implication of virgin birth whatsoever.
You might want to check where the Mazda3 MPS sits on the Nurburgring lap times. Look closely at the company it keeps. It's right between Corvette C5, Honda S2000, Honda NSX and Lotus Exige.
It's faster than the MX5 (by 1 second) and the RX8 (by 4 seconds). The Mazda3 MPS is currently Mazda's fastest production model - despite being FWD.
It's stopping distance (60-0mph or 70-0mph) is also exceptionally short, and comparable to many supercars. Look it up.
Not necessarily, as a parabolic reflector could be followed by a lens (at approximately the focal point) which refocuses the apparent source to infinity again; thereafter the beam would be trivial to 'steer' using a single flat mirror.
They've been doing it planes for years so I don't see why they can't do it in cars.
In my country - the law. There must be a mechanical coupling of the steering wheel to the wheels. Power-assistance is obviously fine, but true drive-by-wire systems aren't legal. Presumably for reliability - if your engine stalls or electrics die you can still steer a power-steered car (though it's hard
labour).
The high end transmissions these days are automated clutches in one form or another. You shift just like normal but the clutch engagement is automatic and (usually) much faster than you could do it yourself. You still chose the shift points but there is no shift pedal - just a stick or paddles. Hate to say it but the clutch pedal is a relic that has no functional reason to exist anymore. It only sticks around because people like it - not because it is actually necessary or even all that useful 99% of the time.
A manual transmission is far cheaper than a conventional auto or new double-clutch systems. That's a pretty big driver. I don't know what it's like in the US, but most automatics in New Zealand carry a price premium of around 10% vs the manual version.
Personally I dislike automatics purely because of the torque converter. I like my revs to directly correspond to wheel speed. Not some vague relationship where it feels like my pedal position is merely a suggestion.
Maybe US-spec Camry with its soft suspension. Other markets get a firmer, more responsive car. From this review, comparing a US-spec hybrid to the local (New Zealand) conventional model:
The Camry hybrid's American-soft suspension settings meant the sedan wallowed its way around every Manfeild bend, which made the conventional model's handling sportscar-sharp by comparison.
Note that down-under, the local Camry would in-turn be generally considered "wallowy" itself vs many of its contemporaries, but smaller sportier cars are the norm down here.
I thought that trains used electric motors powered by diesel generators rather than using diesels alone because electric motors had enough torque to pull a train, while the diesel didn't?
Short answer is electric motors have torque from 0rpm whereas a diesel engine alone can't operate from 0rpm so needs some sort of clutch or slip system. All weighed up, the diesel-electric approach comes out ahead of other mechanisms.
Ferrari are developing a hybrid with conventional mid-mounted engine driving the rear wheels, and in-wheel electric motors up front. The two big challenges are the unsprung mass contributing to poor ride and probably handling, and also that being unsprung the motors are subject to a lot of vibration and shock from the road surface so they take a beating.
I'd be picking the motors might be technically in-wheel (or near enough) but aren't actually unsprung. They'd still likely require a gear reduction anyway, so wouldn't be a direct coupling from motor axle to wheel axle. They'll be "in-wheel" only so much as that is intuitive in a marketing sense i.e. one independent motor per wheel mounted at/near - but not "on" - the wheel axle.
It could do a reasonable scan across the plane in which the speakers are located. A properly-phased stereo signal played across the two speakers would effectively 'scan' horizontally, behaving as a basic phased array. Some proper deconvolution and you could probably get x-resolution to within a few wavelengths - perhaps an inch or so with ultrasonic frequencies.
That's probably sufficient to combine with the webcam to do 'proper' facial recognition, while using the ultrasonic scan to do a quick check on whether it's a flat surface (i.e. photograph) or vaguely head-shaped.
Actually efficiency is dimensionless, it's the proportion of input energy converted into useful output energy. That's not necessarily useful since humans don't perceive energy across the spectrum equally. Efficacy, OTOH, is not dimensionless and is the more useful term as it's the *apparent* amount of light output per energy input (i.e. *lumens* per watt)
The actual news here is that they co-existed with the Maori - it was previously thought they had died out before the Maori arrived. The existence of the Haast's Eagle was well known and there exist Moa bones with massive gouges from being attacked by these Eagles.
It's fairly common for complicated extractions. My top wisdom teeth were removed using local anesthetic in a matter of minutes. I recovered with minor pain for the next day or so, but no real need for any painkillers. My lower wisdom teeth OTOH were removed under IV-administered sedation - not full anesthesia, but I only recall a few minutes of the 75 minute operation - because they were impacted and required being drilled and broken up in my gums before they could be removed. For the next four days, prescription painkillers were my best friends!
Incidentally I've never heard of laughing gas being administered for any procedure, dental or otherwise, here in New Zealand.
Acceleration off-the-line is predominantly determined by power-to-weight (given traction). This is how the low-powered Caterhams and Lotus Elises can hang with the "big boys" using that metric.
Top speed, OTOH is dominated by outright power and drag. Mass features little, hence top speed is typically dominated by heavier cars with massive amounts of power.
Incidentally 60-0, and also cornering, should be dominated by mass & traction, but traction itself is influenced strongly by mass, making traction alone the dominant factor (ignoring aero which is increasingly significant at speed) - which is why almost any car with four good tires can pretty much pull the same braking and cornering (skid-pan) figures of around 1G. if you can find published 60mph-0 distances, you'll find they are usually around the 40 metre mark, almost regardless of the car model.
Not explicitly perhaps, but certain passages read along the lines of "pray for the souls of the dead" - what benefit could that possibly have unless they were in purgatory/limbo? Hell is a one-way trip, and those in Heaven need no such prayer.
Chemical batteries still have much higher energy density (Wh per kg) than capacitors - about ten times higher.
That's not to say that supercaps combined with traditional batteries wouldn't solve such problems - they probably could in cases where you have a low average discharge, but high burst discharge. These new cells would be capable of sustaining high average discharge.
It's only like capacitors in that the discharge is fast. This is still a chemical cell, unlike capacitors which store energy in electric fields. Chemical batteries still have faaaar higher energy density (Wh per kg) than capacitors.
Wikipedia is correct; DC current cannot pass through a capacitor, so it is indeed impedance rather than resistance.
Then by that argument, strictly it should be called reactance, not impedance. Impedance is the "sum" of AC reactance and DC resistance. Besides, DC current can still flow through a capacitor (during charge and discharge) so resistance is a perfectly acceptable - and accurate - term, especially regarding the waste heat generated by charge and discharge.
Secondly I support GP's assertion that output impedance and internal resistance are not at all the same - Look up Norton's equivalence theorem (remembering that an ideal current source has infinite impedance). Then there's the concept of negative feedback in an amplifier, which affects output impedance but not the internal resistance of any device.
HP is a power rating, and power isn't what kills gears - torque is. RC cars & buggies frequently get by with 4-5mm thick nylon gears, with nitro engines that approach 2hp or more. The nylon gears are adequate because they spin at upwards of 10000rpm so have correspondingly low torque requirements.
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For a race car you could use ultracapacitors instead of batteries. How much current can your charge cable handle...?
Not realistic with current capacitor tech. At best, caps can currently store about 1/5th of the capacity of a battery of similar mass. The best production ultracaps are around 30Wh/kg, whereas LiPo batteries are well over 100Wh/kg, and can exceed 200Wh/kg for certain variants.
Well, it's not efficiency for starters, it's efficacy. And "output"/"input" is all a matter of perspective: I don't put a fixed amount of fuel in my car and then want to know how far I can drive. I know how far I must drive, so L/100km gives me consumption and therefore fuel cost of my commute. Hence I can readily estimate weekly, monthly, or yearly fuel cost.
It's also linear: 12L/100km is 20% worse than 10L/100km, and 8L/100km is 20% better, for a known distance that needs to be travelled. 8.33km/L -> 10km/L -> 12.5km/L is not linear. Whether you prefer a linear-proportional scale or inversely-proportional scale in this matter is up to you.
Consider that distance travelled is fixed (it is for me) and therefore distance is the "input", and fuel consumption (or cost) is the "output" - albeit a negative output - and then it makes perfect sense.
IMHO that's all to do with technical reasons of producing and displaying the photos, not inability for the eye to comfortably view them.
of course I didn't believe that it took photos, but to imply that 3d stereoscopic photography is rare is simply untrue, considering 1.5 billion viewmaster disks have been produced.
did you make even one such photo? Know anybody who did?
Aw, didn't mummy let you play with the Viewmaster?
Immaculate conception doesn't refer to the virgin birth (of Christ) but rather the doctrine that Mary herself was born immaculate (free from original sin), which has no implication of virgin birth whatsoever.
You might want to check where the Mazda3 MPS sits on the Nurburgring lap times. Look closely at the company it keeps. It's right between Corvette C5, Honda S2000, Honda NSX and Lotus Exige. It's faster than the MX5 (by 1 second) and the RX8 (by 4 seconds). The Mazda3 MPS is currently Mazda's fastest production model - despite being FWD. It's stopping distance (60-0mph or 70-0mph) is also exceptionally short, and comparable to many supercars. Look it up.
Not necessarily, as a parabolic reflector could be followed by a lens (at approximately the focal point) which refocuses the apparent source to infinity again; thereafter the beam would be trivial to 'steer' using a single flat mirror.
Uh, doppler shift? Is that not how radar guns work?
They've been doing it planes for years so I don't see why they can't do it in cars.
In my country - the law. There must be a mechanical coupling of the steering wheel to the wheels. Power-assistance is obviously fine, but true drive-by-wire systems aren't legal. Presumably for reliability - if your engine stalls or electrics die you can still steer a power-steered car (though it's hard labour).
The high end transmissions these days are automated clutches in one form or another. You shift just like normal but the clutch engagement is automatic and (usually) much faster than you could do it yourself. You still chose the shift points but there is no shift pedal - just a stick or paddles. Hate to say it but the clutch pedal is a relic that has no functional reason to exist anymore. It only sticks around because people like it - not because it is actually necessary or even all that useful 99% of the time.
A manual transmission is far cheaper than a conventional auto or new double-clutch systems. That's a pretty big driver. I don't know what it's like in the US, but most automatics in New Zealand carry a price premium of around 10% vs the manual version.
Personally I dislike automatics purely because of the torque converter. I like my revs to directly correspond to wheel speed. Not some vague relationship where it feels like my pedal position is merely a suggestion.
The Camry hybrid's American-soft suspension settings meant the sedan wallowed its way around every Manfeild bend, which made the conventional model's handling sportscar-sharp by comparison.
Note that down-under, the local Camry would in-turn be generally considered "wallowy" itself vs many of its contemporaries, but smaller sportier cars are the norm down here.
I thought that trains used electric motors powered by diesel generators rather than using diesels alone because electric motors had enough torque to pull a train, while the diesel didn't?
Short answer is electric motors have torque from 0rpm whereas a diesel engine alone can't operate from 0rpm so needs some sort of clutch or slip system. All weighed up, the diesel-electric approach comes out ahead of other mechanisms.
Ferrari are developing a hybrid with conventional mid-mounted engine driving the rear wheels, and in-wheel electric motors up front. The two big challenges are the unsprung mass contributing to poor ride and probably handling, and also that being unsprung the motors are subject to a lot of vibration and shock from the road surface so they take a beating.
I'd be picking the motors might be technically in-wheel (or near enough) but aren't actually unsprung. They'd still likely require a gear reduction anyway, so wouldn't be a direct coupling from motor axle to wheel axle. They'll be "in-wheel" only so much as that is intuitive in a marketing sense i.e. one independent motor per wheel mounted at/near - but not "on" - the wheel axle.
It could do a reasonable scan across the plane in which the speakers are located. A properly-phased stereo signal played across the two speakers would effectively 'scan' horizontally, behaving as a basic phased array. Some proper deconvolution and you could probably get x-resolution to within a few wavelengths - perhaps an inch or so with ultrasonic frequencies.
That's probably sufficient to combine with the webcam to do 'proper' facial recognition, while using the ultrasonic scan to do a quick check on whether it's a flat surface (i.e. photograph) or vaguely head-shaped.
Actually efficiency is dimensionless, it's the proportion of input energy converted into useful output energy. That's not necessarily useful since humans don't perceive energy across the spectrum equally. Efficacy, OTOH, is not dimensionless and is the more useful term as it's the *apparent* amount of light output per energy input (i.e. *lumens* per watt)
The actual news here is that they co-existed with the Maori - it was previously thought they had died out before the Maori arrived. The existence of the Haast's Eagle was well known and there exist Moa bones with massive gouges from being attacked by these Eagles.
It's fairly common for complicated extractions. My top wisdom teeth were removed using local anesthetic in a matter of minutes. I recovered with minor pain for the next day or so, but no real need for any painkillers. My lower wisdom teeth OTOH were removed under IV-administered sedation - not full anesthesia, but I only recall a few minutes of the 75 minute operation - because they were impacted and required being drilled and broken up in my gums before they could be removed. For the next four days, prescription painkillers were my best friends!
Incidentally I've never heard of laughing gas being administered for any procedure, dental or otherwise, here in New Zealand.
Acceleration off-the-line is predominantly determined by power-to-weight (given traction). This is how the low-powered Caterhams and Lotus Elises can hang with the "big boys" using that metric.
Top speed, OTOH is dominated by outright power and drag. Mass features little, hence top speed is typically dominated by heavier cars with massive amounts of power.
Incidentally 60-0, and also cornering, should be dominated by mass & traction, but traction itself is influenced strongly by mass, making traction alone the dominant factor (ignoring aero which is increasingly significant at speed) - which is why almost any car with four good tires can pretty much pull the same braking and cornering (skid-pan) figures of around 1G. if you can find published 60mph-0 distances, you'll find they are usually around the 40 metre mark, almost regardless of the car model.
Not explicitly perhaps, but certain passages read along the lines of "pray for the souls of the dead" - what benefit could that possibly have unless they were in purgatory/limbo? Hell is a one-way trip, and those in Heaven need no such prayer.
Chemical batteries still have much higher energy density (Wh per kg) than capacitors - about ten times higher. That's not to say that supercaps combined with traditional batteries wouldn't solve such problems - they probably could in cases where you have a low average discharge, but high burst discharge. These new cells would be capable of sustaining high average discharge.
It's only like capacitors in that the discharge is fast. This is still a chemical cell, unlike capacitors which store energy in electric fields. Chemical batteries still have faaaar higher energy density (Wh per kg) than capacitors.
Most Bible translations are copyrighted. I think the King James version is about the only [English] translation no longer in copyright.
Wikipedia is correct; DC current cannot pass through a capacitor, so it is indeed impedance rather than resistance.
Then by that argument, strictly it should be called reactance, not impedance. Impedance is the "sum" of AC reactance and DC resistance. Besides, DC current can still flow through a capacitor (during charge and discharge) so resistance is a perfectly acceptable - and accurate - term, especially regarding the waste heat generated by charge and discharge.
Secondly I support GP's assertion that output impedance and internal resistance are not at all the same - Look up Norton's equivalence theorem (remembering that an ideal current source has infinite impedance). Then there's the concept of negative feedback in an amplifier, which affects output impedance but not the internal resistance of any device.
HP is a power rating, and power isn't what kills gears - torque is. RC cars & buggies frequently get by with 4-5mm thick nylon gears, with nitro engines that approach 2hp or more. The nylon gears are adequate because they spin at upwards of 10000rpm so have correspondingly low torque requirements.