Horsepower

[Carrot44]

How does horsepower relate to Cars. GF asked me that anybody got ideas?

 

[crazygal]

Someone (Watts) said 1 horse can produce a certain amount of energy. Your car produces energy as well. Since car engines are more powerful than horses, it would take multiple horses to produce the same amount of power. Ergo, a 200 horsepower engine is as powerful as 200 horses...

and you call yourself a man!

 

[ndee]

IIRC, one horse power != one real horse power.

 

[crazygal]

Perhaps not, but I believe that's where horse power is derived from.

 

[Eli]

It was actually James Watt.

The story goes that Watt was working with ponies lifting coal at a coal mine, and he wanted a way to talk about the power available from one of these animals. He found that, on average, a mine pony could do 22,000 foot-pounds of work in a minute. He then increased that number by 50 percent and pegged the measurement of horsepower at 33,000 foot-pounds of work in one minute. It is that arbitrary unit of measure that has made its way down through the centuries and now appears on your car, your lawn mower, your chain saw and even in some cases your vacuum cleaner!

 

[Jzero]

Originally posted by: ndee
IIRC, one horse power != one real horse power.

It was actually James Watt. It is very likely that he actually did his original measurement with donkeys, but decided that "horsepower" sounded better than "asspower."

 

[0roo0roo]

determines your top speed more or less.

 

[ndee]

Originally posted by: crazygal
Perhaps not, but I believe that's where horse power is derived from.

yeah, originally but my physics teacher told us once it's not really like 1 real horse = 1 horse power. Don't remember why though.

 

[ndee]

Originally posted by: 0roo0roo
determines your top speed more or less.

RC Cars can go pretty fast with 1.95HP

 

[Vic]

In older times, horses were used to turn dynamos, which generated electricity or ground grain (edit: or lifted loads out of mines ). A horsepower is the ability to lift 33,000 pounds one foot in one minute. The unit of measurement was introduced by James Watt, who invented the first practical steam engine ~200 years ago. In electrical terms, a horsepower equals 745.699 watts. In cars, horsepower equals (torque*rpm)/5252.

 

[notfred]

Horse power is the average work a horse does over the course of an 8 hour day, not the maximum amount that the horse can do when it's trying it's hardest.

 

[Eli]

Originally posted by: Jzero

Originally posted by: ndee
IIRC, one horse power != one real horse power.

It was actually James Watt. It is very likely that he actually did his original measurement with donkeys, but decided that "horsepower" sounded better than "asspower."

LMAO....

 

[Eli]

Originally posted by: notfred
Horse power is the average work a horse does over the course of an 8 hour day, not the maximum amount that the horse can do when it's trying it's hardest.

Nope.... It's based on the average weight a horse can lift in one minute.

 

[LS20]

lets keep it simple the more the better

 

[Bignate603]

Originally posted by: Eli

Originally posted by: notfred
Horse power is the average work a horse does over the course of an 8 hour day, not the maximum amount that the horse can do when it's trying it's hardest.

Nope.... It's based on the average weight a horse can lift in one minute.

Unfortunatly notfred, I think I'll have to side with Eli on this one...

 

[notfred]

Originally posted by: Eli

Originally posted by: notfred
Horse power is the average work a horse does over the course of an 8 hour day, not the maximum amount that the horse can do when it's trying it's hardest.

Nope.... It's based on the average weight a horse can lift in one minute.

Maybe he was measuring one minute at a time, but the measurement is based on horse doing an average amount of work, as it would be doing when working all day, not one minute of all-out exhausting work.

 

[Eli]

Originally posted by: notfred

Originally posted by: Eli

Originally posted by: notfred
Horse power is the average work a horse does over the course of an 8 hour day, not the maximum amount that the horse can do when it's trying it's hardest.

Nope.... It's based on the average weight a horse can lift in one minute.

Maybe he was measuring one minute at a time, but the measurement is based on horse doing an average amount of work, as it would be doing when working all day, not one minute of all-out exhausting work.

Heh..

What horsepower means is this: In Watt's judgement, one horse can do 33,000 foot-pounds of work every minute. So, imagine a horse raising coal out of a coal mine as shown above. A horse exerting 1 horsepower can raise 330 pounds of coal 100 feet in a minute, or 33 pounds of coal 1,000 feet in one minute, or 1,000 pounds 33 feet in one minute. You can make up whatever combination of feet and pounds you like. As long as the product is 33,000 foot-pounds in one minute, you have a horsepower.

You can probably imagine that you would not want to load 33,000 pounds of coal in the bucket and ask the horse to move it 1 foot in a minute because the horse couldn't budge that big a load. You can probably also imagine that you would not want to put 1 pound of coal in the bucket and ask the horse to run 33,000 feet in one minute, since that translates into 375 miles per hour and horses can't run that fast. However, if you have read How a Block and Tackle Works, you know that with a block and tackle you can easily trade perceived weight for distance using an arrangement of pulleys. So you could create a block and tackle system that puts a comfortable amount of weight on the horse at a comfortable speed no matter how much weight is actually in the bucket.

Horsepower can be converted into other units as well. For example:

1 horsepower is equivalent to 746 watts. So if you took a 1-horsepower horse and put it on a treadmill, it could operate a generator producing a continuous 746 watts.

1 horsepower (over the course of an hour) is equivalent to 2,545 BTU (British thermal units). If you took that 746 watts and ran it through an electric heater for an hour, it would produce 2,545 BTU (where a BTU is the amount of energy needed to raise the temperature of 1 pound of water 1 degree F).

One BTU is equal to 1,055 joules, or 252 gram-calories or 0.252 food Calories. Presumably, a horse producing 1 horsepower would burn 641 Calories in one hour if it were 100-percent efficient.

 

[MercenaryForHire]

All I know is that the more stickers on your car, the more HP you have.



- M4H

 

[notfred]

Originally posted by: Eli

Originally posted by: notfred

Originally posted by: Eli

Originally posted by: notfred
Horse power is the average work a horse does over the course of an 8 hour day, not the maximum amount that the horse can do when it's trying it's hardest.

Nope.... It's based on the average weight a horse can lift in one minute.

Maybe he was measuring one minute at a time, but the measurement is based on horse doing an average amount of work, as it would be doing when working all day, not one minute of all-out exhausting work.

Heh..

What horsepower means is this: In Watt's judgement, one horse can do 33,000 foot-pounds of work every minute. So, imagine a horse raising coal out of a coal mine as shown above. A horse exerting 1 horsepower can raise 330 pounds of coal 100 feet in a minute, or 33 pounds of coal 1,000 feet in one minute, or 1,000 pounds 33 feet in one minute. You can make up whatever combination of feet and pounds you like. As long as the product is 33,000 foot-pounds in one minute, you have a horsepower.

You can probably imagine that you would not want to load 33,000 pounds of coal in the bucket and ask the horse to move it 1 foot in a minute because the horse couldn't budge that big a load. You can probably also imagine that you would not want to put 1 pound of coal in the bucket and ask the horse to run 33,000 feet in one minute, since that translates into 375 miles per hour and horses can't run that fast. However, if you have read How a Block and Tackle Works, you know that with a block and tackle you can easily trade perceived weight for distance using an arrangement of pulleys. So you could create a block and tackle system that puts a comfortable amount of weight on the horse at a comfortable speed no matter how much weight is actually in the bucket.

Horsepower can be converted into other units as well. For example:

1 horsepower is equivalent to 746 watts. So if you took a 1-horsepower horse and put it on a treadmill, it could operate a generator producing a continuous 746 watts.

1 horsepower (over the course of an hour) is equivalent to 2,545 BTU (British thermal units). If you took that 746 watts and ran it through an electric heater for an hour, it would produce 2,545 BTU (where a BTU is the amount of energy needed to raise the temperature of 1 pound of water 1 degree F).

One BTU is equal to 1,055 joules, or 252 gram-calories or 0.252 food Calories. Presumably, a horse producing 1 horsepower would burn 641 Calories in one hour if it were 100-percent efficient.

Yes, measuring using a horse working at it's regular pace, as it would do when loading coal 8 hours a day. I'm saying they didn't stop loading coal, bring in a fresh horse, have it run it's ass off for 60 seconds then let it collapse on the floor in exhaustion. The idea was to measure the amount of power that a workhorse exerts. Not the maximum amount of power that a horse could exert under non-realisitc circumstances.

 

[Malladine]

You tink one 200hp car could pull as much as 200 horses?

*snicker*

 

[Kntx]

not 200 horses pulling their hardest... but pulling at an average rate

No it couldn't, not enough traction.

 

[Carrot44]

Thanks :beer:

 

[OS]

I kind of like watts more than HP as a way to measure power output. It gives a perspective of how much power a car motor is worth relative to household/industrial appliances and stuff. Usually we think of a 100 HP car as pretty underpowered, but that's actually still a fair amount of power. You could probably run a whole house off that much power.

I remember reading something online about a 1 megawatt skyline project. Apparently that's 1341 HP. :Q

 

[Carrot44]

Hey my car engine is rated at 75 HP!

 

[Vortex22]

Originally posted by: Carrot39
Hey my car engine is rated at 75 HP!

Uhh.. Geo Metro?