RPM stands for revolutions per minute.
Sounds like TIME to me!
Sounds like TIME to me!
Low end torque is low end horsepower
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Originally Posted By: Ben99GT
Originally Posted By: mechtech2
It is why a CVT trans car at full throttle keeps the RPM at the torque peak, and varies the gearing.
Nope, a CVT at WOT will rev to the point of peak horsepower everytime.
It may eventually raise RPM to it's peak HP, if maximum top speed is sought.
But it hangs in the torque peak for max acceleration .
Originally Posted By: mechtech2
It is why a CVT trans car at full throttle keeps the RPM at the torque peak, and varies the gearing.
Nope, a CVT at WOT will rev to the point of peak horsepower everytime.
It may eventually raise RPM to it's peak HP, if maximum top speed is sought.
But it hangs in the torque peak for max acceleration .
Originally Posted By: Stelth1
In 2) horsepower is like wattage? IOW, the amount of electrical power used is measured in watt-hours, so the amount of IC engine power used would be horsepower-hours? (or possibly watt hours, depending on what scale you're using)
Horsepower and watts are both units of power, and 1HP equal 746 watts. Watt-hours and and horsepower hours are not units of power, but energy or work. Power is work per time. if you multiply a power unit like HP by a time unit by seconds, you get back to units of work.
In 2) horsepower is like wattage? IOW, the amount of electrical power used is measured in watt-hours, so the amount of IC engine power used would be horsepower-hours? (or possibly watt hours, depending on what scale you're using)
Horsepower and watts are both units of power, and 1HP equal 746 watts. Watt-hours and and horsepower hours are not units of power, but energy or work. Power is work per time. if you multiply a power unit like HP by a time unit by seconds, you get back to units of work.
Originally Posted By: mechtech2
Originally Posted By: Ben99GT
Originally Posted By: mechtech2
It is why a CVT trans car at full throttle keeps the RPM at the torque peak, and varies the gearing.
Nope, a CVT at WOT will rev to the point of peak horsepower everytime.
It may eventually raise RPM to it's peak HP, if maximum top speed is sought.
But it hangs in the torque peak for max acceleration .
Max horsepower will yield max acceleration. This link works out an example for a CVT.
http://www.v8914.com/Horsepower-v-torque.htm
Originally Posted By: Ben99GT
Originally Posted By: mechtech2
It is why a CVT trans car at full throttle keeps the RPM at the torque peak, and varies the gearing.
Nope, a CVT at WOT will rev to the point of peak horsepower everytime.
It may eventually raise RPM to it's peak HP, if maximum top speed is sought.
But it hangs in the torque peak for max acceleration .
Max horsepower will yield max acceleration. This link works out an example for a CVT.
http://www.v8914.com/Horsepower-v-torque.htm
Originally Posted By: mechtech2
It may eventually raise RPM to it's peak HP, if maximum top speed is sought.
But it hangs in the torque peak for max acceleration .
At WOT, no CVT will hang at the RPM at which peak engine torque occurs for any meaningful period of time. All of these manufacturers are programming their CVTs to ramp up to the RPM of peak HP as quick as possible and then maintain that RPM for the duration of the run.
It may eventually raise RPM to it's peak HP, if maximum top speed is sought.
But it hangs in the torque peak for max acceleration .
At WOT, no CVT will hang at the RPM at which peak engine torque occurs for any meaningful period of time. All of these manufacturers are programming their CVTs to ramp up to the RPM of peak HP as quick as possible and then maintain that RPM for the duration of the run.
Originally Posted By: OVERK1LL
OK, but then this is where we determine how pedantic we want to be here
1. In order to have RPM, we must have force (torque) and if any force is being applied and it causes movement, we are performing work, no matter how minute that amount of work is to create that RPM.
That's just silly, Overkill, science IS pedantic. RPM are just units of angular velocity, does not imply anything more!
OK, but then this is where we determine how pedantic we want to be here
1. In order to have RPM, we must have force (torque) and if any force is being applied and it causes movement, we are performing work, no matter how minute that amount of work is to create that RPM.
That's just silly, Overkill, science IS pedantic. RPM are just units of angular velocity, does not imply anything more!
Originally Posted By: PeteTheFarmer
Horsepower and watts are both units of power, and 1HP equal 746 watts. Watt-hours and and horsepower hours are not units of power, but energy or work. Power is work per time. if you multiply a power unit like HP by a time unit by seconds, you get back to units of work.
Refreshing to see someone who knows what they're talking about
Horsepower and watts are both units of power, and 1HP equal 746 watts. Watt-hours and and horsepower hours are not units of power, but energy or work. Power is work per time. if you multiply a power unit like HP by a time unit by seconds, you get back to units of work.
Refreshing to see someone who knows what they're talking about
time for my idea. horsepower is power measured over time. Torque is power at any given moment. think iam wrong? read what James Watt said about it.
Originally Posted By: PeteTheFarmer
Originally Posted By: Stelth1
In 2) horsepower is like wattage? IOW, the amount of electrical power used is measured in watt-hours, so the amount of IC engine power used would be horsepower-hours? (or possibly watt hours, depending on what scale you're using)
Horsepower and watts are both units of power, and 1HP equal 746 watts. Watt-hours and and horsepower hours are not units of power, but energy or work. Power is work per time. if you multiply a power unit like HP by a time unit by seconds, you get back to units of work.
That's what I was saying, although perhaps not as precisely as you've put it.
Originally Posted By: Stelth1
In 2) horsepower is like wattage? IOW, the amount of electrical power used is measured in watt-hours, so the amount of IC engine power used would be horsepower-hours? (or possibly watt hours, depending on what scale you're using)
Horsepower and watts are both units of power, and 1HP equal 746 watts. Watt-hours and and horsepower hours are not units of power, but energy or work. Power is work per time. if you multiply a power unit like HP by a time unit by seconds, you get back to units of work.
That's what I was saying, although perhaps not as precisely as you've put it.
Originally Posted By: morris
time for my idea. horsepower is power measured over time. Torque is power at any given moment. think iam wrong? read what James Watt said about it.
Yes, you are wrong. Mr. Watt must be turning in his grave.
Horsepower is not power measured over time. Horsepower is power.
Power = Work performed over a unit of time.
Work = Force x distance.
Therefore Power = (Force x Distance) / Time.
time for my idea. horsepower is power measured over time. Torque is power at any given moment. think iam wrong? read what James Watt said about it.
Yes, you are wrong. Mr. Watt must be turning in his grave.
Horsepower is not power measured over time. Horsepower is power.
Power = Work performed over a unit of time.
Work = Force x distance.
Therefore Power = (Force x Distance) / Time.
have you read his work? you answered my Q
http://www.magnet.fsu.edu/education/tutorials/pioneers/watt.html
Watt established one unit of horsepower to be equivalent to 33,000 pounds lifted one foot per minute. I
Watt established one unit of horsepower to be equivalent to 33,000 pounds lifted one foot per minute. I
OVERKILL
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Originally Posted By: Kiwi_ME
Originally Posted By: OVERK1LL
OK, but then this is where we determine how pedantic we want to be here
1. In order to have RPM, we must have force (torque) and if any force is being applied and it causes movement, we are performing work, no matter how minute that amount of work is to create that RPM.
That's just silly, Overkill, science IS pedantic. RPM are just units of angular velocity, does not imply anything more!
I don't see how it is silly?
In the context of the internal combustion engine, is it possible to have RPM > 0 without force?
(I'm not trying to be a smart a$$ here)
I'm not arguing what the definition of RPM is. I'm saying that any RPM > 0 in the context of an IC engine implies work is being performed. Because in order to have crankshaft movement (measured in RPM), force is being applied.
If you can prove otherwise or explain to my why I'm out to lunc here, I'm more than willing to listen!
Originally Posted By: OVERK1LL
OK, but then this is where we determine how pedantic we want to be here
1. In order to have RPM, we must have force (torque) and if any force is being applied and it causes movement, we are performing work, no matter how minute that amount of work is to create that RPM.
That's just silly, Overkill, science IS pedantic. RPM are just units of angular velocity, does not imply anything more!
I don't see how it is silly?
In the context of the internal combustion engine, is it possible to have RPM > 0 without force?
(I'm not trying to be a smart a$$ here)
I'm not arguing what the definition of RPM is. I'm saying that any RPM > 0 in the context of an IC engine implies work is being performed. Because in order to have crankshaft movement (measured in RPM), force is being applied.
If you can prove otherwise or explain to my why I'm out to lunc here, I'm more than willing to listen!
Originally Posted By: morris
http://www.magnet.fsu.edu/education/tutorials/pioneers/watt.html
Watt established one unit of horsepower to be equivalent to 33,000 pounds lifted one foot per minute.
Which is not the same as "horsepower is power measured over time." that you stated earlier.
The "33,000 pounds lifted one foot" is work, not power. Once you divide work over time, then you get power.
http://www.magnet.fsu.edu/education/tutorials/pioneers/watt.html
Watt established one unit of horsepower to be equivalent to 33,000 pounds lifted one foot per minute.
Which is not the same as "horsepower is power measured over time." that you stated earlier.
The "33,000 pounds lifted one foot" is work, not power. Once you divide work over time, then you get power.
Originally Posted By: Quattro Pete
Originally Posted By: morris
time for my idea. horsepower is power measured over time. Torque is power at any given moment. think iam wrong? read what James Watt said about it.
Yes, you are wrong. Mr. Watt must be turning in his grave.
Horsepower is not power measured over time. Horsepower is power.
Power = Work performed over a unit of time.
Work = Force x distance.
Therefore Power = (Force x Distance) / Time.
But horsepower has all 3 in it's equation. (33,000lbs (Force)x 1ft (distance))/min (time) or (550lbs x 1ft)/second or (tq x RPM)/5252. Oversimplified and maybe slightly mislabled but the point is still correct.
Torque in lb ft is a unit of work and horsepower is work over a period or time or rate (Torque x RPM).
Nevermind I just noticed what morris originally said and what you were correcting. horsepower is power like you said.
Originally Posted By: morris
time for my idea. horsepower is power measured over time. Torque is power at any given moment. think iam wrong? read what James Watt said about it.
Yes, you are wrong. Mr. Watt must be turning in his grave.
Horsepower is not power measured over time. Horsepower is power.
Power = Work performed over a unit of time.
Work = Force x distance.
Therefore Power = (Force x Distance) / Time.
But horsepower has all 3 in it's equation. (33,000lbs (Force)x 1ft (distance))/min (time) or (550lbs x 1ft)/second or (tq x RPM)/5252. Oversimplified and maybe slightly mislabled but the point is still correct.
Torque in lb ft is a unit of work and horsepower is work over a period or time or rate (Torque x RPM).
Nevermind I just noticed what morris originally said and what you were correcting. horsepower is power like you said.
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There are all sorts of references showing CVTs run at torque peak.
Like Toyota, where the engine runs at about 4,000RPM peak torque, NOT the 6,000+ RPM of max HP!
[I was just with my neighbor's.]
Like Toyota, where the engine runs at about 4,000RPM peak torque, NOT the 6,000+ RPM of max HP!
[I was just with my neighbor's.]
Originally Posted By: mechtech2
There are all sorts of references showing CVTs run at torque peak.
Like Toyota, where the engine runs at about 4,000RPM peak torque, NOT the 6,000+ RPM of max HP!
[I was just with my neighbor's.]
You're right, at half throttle it will probably hang around peak torque.
WOT, peak horsepower, assuming the CVT isn't equipped with some kind of phony tiptronic function.
Couple more examples...
There are all sorts of references showing CVTs run at torque peak.
Like Toyota, where the engine runs at about 4,000RPM peak torque, NOT the 6,000+ RPM of max HP!
[I was just with my neighbor's.]
You're right, at half throttle it will probably hang around peak torque.
WOT, peak horsepower, assuming the CVT isn't equipped with some kind of phony tiptronic function.
Couple more examples...
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