It sounds like you too need to learn the difference between power and energy. Energy (Wh) = Power (W) x Time (h). There really is a time component in there.
There's everything you need to know in Wikipedia's article on the unit.
Washing machine energy usage.
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It sounds like you too need to learn the difference between power and energy. Energy (Wh) = Power (W) x Time (h). There really is a time component in there.
There's everything you need to know in Wikipedia's article on the unit.Sponsored Links
As I'm sure you know, there are 3600 seconds in an hour. Typo?
So 1 watt-hour = 3600 J = 3.6 kJ.
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Yes typo, but still shows the point Joule / second * hour = 3600 Joules.
Confirms what I saidIt sounds like you too need to learn the difference between power and energy. Energy (Wh) = Power (W) x Time (h). There really is a time component in there.
There is no time involved, it is simply a way of making the unit smaller, it seems for SI units it needs to be power or route of ³ so there is no centimetre or erg in SI units, but we don't it seems need to work in 10's, 980 and 4.7 and 60 still used, kg to newton, Joules to calories, and seconds in hours or degrees.
To my mind 32 pounds in a Slug made sense, links to binary system but newton seems to have some gravity
I blame the French had they got their sums right, a nautical mile and a kilometre would be the same. But problem with a nautical mile is it changes depending on altitude/depth. It is also its good point.
So you've overlooked the 'for one hour' bit then...?
This is starting to feel like a discussion amongst drunks.
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OK, I see you have edited #45. I can't remember what else you said originally, but it wasn't right, out by some power of 10.
Also to get down to basic dimensions M mass, L length, T time, energy is M*L^2*T^-2 so there is time in there.
Watt = Joule per second, so a kWh since there 3600 seconds in an hour = 3600 kJ there is no time. Seems daft to have hour in the name when nothing to do with time.
I tried to measure out of interest what power items use, thesehave been around for some time, and I was a one time trying to save power used, however although one could see with a kettle the power used to boil, the washing machine was virtually impossible.
I have just ordered one of that exact model, to replace a much older one which has an impossibly tiny display.
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Yes torque to power uses 2πNT/33,000 in old money. Did the calculation that many times, did not need to look it up. Energy when I was at school was two types, dynamic and potential, but that was 60 years ago. It can't be made or destroyed (not quite true, but OK for this discussion) but can be converted. The SI unit is the joule but there are other units kW.h, BTU, calorie, eV, erg, foot-pound etc.
More here Note the dot . means x not ÷ .
It is supplied by the Energy sector as gas, oil and electric and with electric the speed at which it is provided is measured in watts or kilo-watts.
However in the home the way to measure is normally in amps, as our volts are fixed at 230 volt or 12 volt or 48 volt etc.
So my e-bike has a 12 Ah battery at 48 volt, or 2073600 Joules, rather a big number so easier to say 576 watt.hour. Bosch mid engine e-bikes do batteries of 300, 400, and 500 watt.hour in the main 36 volt.
It does cause confusion where one is called 12 Ah and another 500 watt.hour. But the watt.hour is easier to work with, 250 watt means 2 hours at maximum output, although never will be maximum output at 16 MPH maximum speed that would be 32 miles, but in real terms looking at more like 120 miles, I have never completely exhausted my battery.
But a Wh or kWh has no time connected to it, it makes it easy to relate to how much energy will be used, but with my 576 Wh battery it does not matter if I wait 1 hour or 100 hours, unless I ride my bike it will still have same energy stored.
More here Note the dot . means x not ÷ .
It is supplied by the Energy sector as gas, oil and electric and with electric the speed at which it is provided is measured in watts or kilo-watts.
However in the home the way to measure is normally in amps, as our volts are fixed at 230 volt or 12 volt or 48 volt etc.
So my e-bike has a 12 Ah battery at 48 volt, or 2073600 Joules, rather a big number so easier to say 576 watt.hour. Bosch mid engine e-bikes do batteries of 300, 400, and 500 watt.hour in the main 36 volt.
It does cause confusion where one is called 12 Ah and another 500 watt.hour. But the watt.hour is easier to work with, 250 watt means 2 hours at maximum output, although never will be maximum output at 16 MPH maximum speed that would be 32 miles, but in real terms looking at more like 120 miles, I have never completely exhausted my battery.
But a Wh or kWh has no time connected to it, it makes it easy to relate to how much energy will be used, but with my 576 Wh battery it does not matter if I wait 1 hour or 100 hours, unless I ride my bike it will still have same energy stored.
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Might have been a good idea if you had
For torque T (lb.ft), power (hp) = rpm*2*pi*T/33000
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Yes OK tipo missed the NMight have been a good idea if you had
For torque T (lb.ft), power (hp) = rpm*2*pi*T/33000
But in your edit you've still got too many 2s in there. N should have replaced the 2nd one.
Incidentally I don't think much of how pi looks on this site. Clicking the button, it looks OK, but when you use it, it's more like an n. I prefer to type it.
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Yep corrected, missed it.
OK, got there!
BTW did anybody ask for shaft power calculation? I can't see anything, and it won't help the OP much
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The problem seems to be use of H in KW.h, as h stands for hour it seems people think it is related to time. However any number divided by seconds and times by hours is simply 3600 times smaller. X/(X x 3600) = 1/3600 the X cancels out. Simple maths.
Simple maths, completely incorrect conclusions. I give up as I'm at risk of falling for your trolling.
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