How many litres of gaseous helium would it take to lift 80 kg on Earth?
$begingroup$
I have dragons in mind for my world, but I'm trying to find logic in how would a medium-sized anything fly off and still be a danger to humans.
So far, I have a lizard-like cheetah with wings, hollow bones and very strong legs but I still doubt it would be able to fly if it had over 60 kg. So anyway I devised a plan for that, so if anyone has knowledge of physics and such that could answer the question I would be very grateful, thanks.
physics chemistry flight
edited Jan 25 at 22:32
Loong
258312
asked Jan 25 at 16:52
Alright itsCROAlright itsCRO
242
$endgroup$
|
show 5 more comments
$begingroup$
I have dragons in mind for my world, but I'm trying to find logic in how would a medium-sized anything fly off and still be a danger to humans.
So far, I have a lizard-like cheetah with wings, hollow bones and very strong legs but I still doubt it would be able to fly if it had over 60 kg. So anyway I devised a plan for that, so if anyone has knowledge of physics and such that could answer the question I would be very grateful, thanks.
physics chemistry flight
edited Jan 25 at 22:32
Loong
258312
asked Jan 25 at 16:52
Alright itsCROAlright itsCRO
242
$endgroup$
$begingroup$
Welcome to Worldbuilding! If you have a moment, please take the tour and visit the help center to learn more about the site. You may also find Worldbuilding Meta and The Sandbox useful. Here is a meta post on the culture and style of Worldbuilding.SE, just to help you understand our scope and methods, and how we do things here. Have fun!
$endgroup$
– Gryphon
Jan 25 at 17:06
5
$begingroup$
We know that there were flying dinosaurs weighting 145kg or more so there's no reason your dinosaur at 60 or 80kgs could not fly without using buoyancy.
$endgroup$
– Tim B♦
Jan 25 at 17:13
1
$begingroup$
@TimB pterosaurs are not dinosaurs, but that is a good low end mass estimate for Quetzalcoatlus. the largest flying dinosaur aka bird was around 70kg.
$endgroup$
– John
Jan 25 at 17:33
$begingroup$
There is a rather useful calculator here - omnicalculator.com/everyday-life/helium-balloons
$endgroup$
– chasly from UK
Jan 25 at 20:45
$begingroup$
This seems like a pure real-world physics question to me. Since we already have a site for those, I feel like this question should be migrated there.
$endgroup$
– Ilmari Karonen
Jan 25 at 21:11
|
show 5 more comments
$begingroup$
I have dragons in mind for my world, but I'm trying to find logic in how would a medium-sized anything fly off and still be a danger to humans.
So far, I have a lizard-like cheetah with wings, hollow bones and very strong legs but I still doubt it would be able to fly if it had over 60 kg. So anyway I devised a plan for that, so if anyone has knowledge of physics and such that could answer the question I would be very grateful, thanks.
physics chemistry flight
edited Jan 25 at 22:32
Loong
258312
asked Jan 25 at 16:52
Alright itsCROAlright itsCRO
242
$endgroup$
I have dragons in mind for my world, but I'm trying to find logic in how would a medium-sized anything fly off and still be a danger to humans.
So far, I have a lizard-like cheetah with wings, hollow bones and very strong legs but I still doubt it would be able to fly if it had over 60 kg. So anyway I devised a plan for that, so if anyone has knowledge of physics and such that could answer the question I would be very grateful, thanks.
physics chemistry flight
physics chemistry flight
edited Jan 25 at 22:32
Loong
258312
asked Jan 25 at 16:52
Alright itsCROAlright itsCRO
242
edited Jan 25 at 22:32
Loong
258312
asked Jan 25 at 16:52
Alright itsCROAlright itsCRO
242
edited Jan 25 at 22:32
Loong
258312
edited Jan 25 at 22:32
Loong
258312
edited Jan 25 at 22:32
Loong
258312
258312
asked Jan 25 at 16:52
Alright itsCROAlright itsCRO
242
asked Jan 25 at 16:52
Alright itsCROAlright itsCRO
242
asked Jan 25 at 16:52
Alright itsCROAlright itsCRO
242
242
$begingroup$
Welcome to Worldbuilding! If you have a moment, please take the tour and visit the help center to learn more about the site. You may also find Worldbuilding Meta and The Sandbox useful. Here is a meta post on the culture and style of Worldbuilding.SE, just to help you understand our scope and methods, and how we do things here. Have fun!
$endgroup$
– Gryphon
Jan 25 at 17:06
5
$begingroup$
We know that there were flying dinosaurs weighting 145kg or more so there's no reason your dinosaur at 60 or 80kgs could not fly without using buoyancy.
$endgroup$
– Tim B♦
Jan 25 at 17:13
1
$begingroup$
@TimB pterosaurs are not dinosaurs, but that is a good low end mass estimate for Quetzalcoatlus. the largest flying dinosaur aka bird was around 70kg.
$endgroup$
– John
Jan 25 at 17:33
$begingroup$
There is a rather useful calculator here - omnicalculator.com/everyday-life/helium-balloons
$endgroup$
– chasly from UK
Jan 25 at 20:45
$begingroup$
This seems like a pure real-world physics question to me. Since we already have a site for those, I feel like this question should be migrated there.
$endgroup$
– Ilmari Karonen
Jan 25 at 21:11
|
show 5 more comments
$begingroup$
Welcome to Worldbuilding! If you have a moment, please take the tour and visit the help center to learn more about the site. You may also find Worldbuilding Meta and The Sandbox useful. Here is a meta post on the culture and style of Worldbuilding.SE, just to help you understand our scope and methods, and how we do things here. Have fun!
$endgroup$
– Gryphon
Jan 25 at 17:06
5
$begingroup$
We know that there were flying dinosaurs weighting 145kg or more so there's no reason your dinosaur at 60 or 80kgs could not fly without using buoyancy.
$endgroup$
– Tim B♦
Jan 25 at 17:13
1
$begingroup$
@TimB pterosaurs are not dinosaurs, but that is a good low end mass estimate for Quetzalcoatlus. the largest flying dinosaur aka bird was around 70kg.
$endgroup$
– John
Jan 25 at 17:33
$begingroup$
There is a rather useful calculator here - omnicalculator.com/everyday-life/helium-balloons
$endgroup$
– chasly from UK
Jan 25 at 20:45
$begingroup$
This seems like a pure real-world physics question to me. Since we already have a site for those, I feel like this question should be migrated there.
$endgroup$
– Ilmari Karonen
Jan 25 at 21:11
$begingroup$
Welcome to Worldbuilding! If you have a moment, please take the tour and visit the help center to learn more about the site. You may also find Worldbuilding Meta and The Sandbox useful. Here is a meta post on the culture and style of Worldbuilding.SE, just to help you understand our scope and methods, and how we do things here. Have fun!
$endgroup$
– Gryphon
Jan 25 at 17:06
$begingroup$
Welcome to Worldbuilding! If you have a moment, please take the tour and visit the help center to learn more about the site. You may also find Worldbuilding Meta and The Sandbox useful. Here is a meta post on the culture and style of Worldbuilding.SE, just to help you understand our scope and methods, and how we do things here. Have fun!
$endgroup$
– Gryphon
Jan 25 at 17:06
5
5
$begingroup$
We know that there were flying dinosaurs weighting 145kg or more so there's no reason your dinosaur at 60 or 80kgs could not fly without using buoyancy.
$endgroup$
– Tim B♦
Jan 25 at 17:13
$begingroup$
We know that there were flying dinosaurs weighting 145kg or more so there's no reason your dinosaur at 60 or 80kgs could not fly without using buoyancy.
$endgroup$
– Tim B♦
Jan 25 at 17:13
1
1
$begingroup$
@TimB pterosaurs are not dinosaurs, but that is a good low end mass estimate for Quetzalcoatlus. the largest flying dinosaur aka bird was around 70kg.
$endgroup$
– John
Jan 25 at 17:33
$begingroup$
@TimB pterosaurs are not dinosaurs, but that is a good low end mass estimate for Quetzalcoatlus. the largest flying dinosaur aka bird was around 70kg.
$endgroup$
– John
Jan 25 at 17:33
$begingroup$
There is a rather useful calculator here - omnicalculator.com/everyday-life/helium-balloons
$endgroup$
– chasly from UK
Jan 25 at 20:45
$begingroup$
There is a rather useful calculator here - omnicalculator.com/everyday-life/helium-balloons
$endgroup$
– chasly from UK
Jan 25 at 20:45
$begingroup$
This seems like a pure real-world physics question to me. Since we already have a site for those, I feel like this question should be migrated there.
$endgroup$
– Ilmari Karonen
Jan 25 at 21:11
$begingroup$
This seems like a pure real-world physics question to me. Since we already have a site for those, I feel like this question should be migrated there.
$endgroup$
– Ilmari Karonen
Jan 25 at 21:11
|
show 5 more comments
3 Answers
3
active
oldest
votes
$begingroup$
For a back-of-the-envelope calculation the rule of thumb is that you need one cubic meter (1000 liters) of hydrogen or helium to lift one kilogram; so for 80 kilograms you need about 80 cubic meters (80,000 liters) of lifting gas.
For a more detailed calculation:
The average density of air at sea level is about 1.2 kg/m³.
The density of helium at 1 atmosphere pressure and 0°C temperature (that's called "standard temperature and pressure", STP) is about 0.18 kg/m³.
The lifting force is the difference between the weight of a volume of helium and the same volume of air, or 1.02 kg/m³.
For 80 kg you need 80 / 1.02 = 78.4 m³ of helium.
For a quick comparison, that's quite comparable with the capacity of a large railroad tank wagon, and about 15% more than the internal volume of a standard 40-foot (12.2 meters) intermodal container:
A stack of standard 40-foot (12.2 meters) intermodal containers. Each container has an internal volume of about 68 cubic meters. Photograph by Martini171, available on Wikimedia under the CC BY-SA 3.0 Unported license.
answered Jan 25 at 17:18
AlexPAlexP
39.2k789153
$endgroup$
add a comment |
$begingroup$
I still doubt it would be able to fly if it had over 60kgs
Helium has a lifting force of one gram per liter. For a 60kg person or animal, you will therefore 60,000 liters. That is 15,850.323 gallons for americans.
The first thing that comes to my mind when I think about 60,000 liters is that it's the usual volume capacity for yhese trucks:
Also notice that flying this way may be very hard. Larry Walters comes to mind.
answered Jan 25 at 17:06
RenanRenan
49.5k13115248
$endgroup$
1
$begingroup$
Thatsalottahelium....
$endgroup$
– JBH
Jan 25 at 17:22
add a comment |
$begingroup$
it would theoretically take 115920 cubic feet of helium to lig=ft 80 kilograms.
Because the difference in the up and downforce is 0.069 pounds. each cubic foot of helium could lift 0.069 pounds. In order to lift a single kilogram, you would need 1449 cubic feet of helium.
Now we have to transfer the cubic feet to liters.
1 cubic foot= 28 litres
115920x28
Theoretically, it would take 3245760 liters to lift 80 kilograms.
answered Jan 25 at 23:15
Rowyn AllowayRowyn Alloway
6321216
$endgroup$
add a comment |
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3 Answers
3
active
oldest
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3 Answers
3
active
oldest
votes
active
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active
oldest
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$begingroup$
For a back-of-the-envelope calculation the rule of thumb is that you need one cubic meter (1000 liters) of hydrogen or helium to lift one kilogram; so for 80 kilograms you need about 80 cubic meters (80,000 liters) of lifting gas.
For a more detailed calculation:
The average density of air at sea level is about 1.2 kg/m³.
The density of helium at 1 atmosphere pressure and 0°C temperature (that's called "standard temperature and pressure", STP) is about 0.18 kg/m³.
The lifting force is the difference between the weight of a volume of helium and the same volume of air, or 1.02 kg/m³.
For 80 kg you need 80 / 1.02 = 78.4 m³ of helium.
For a quick comparison, that's quite comparable with the capacity of a large railroad tank wagon, and about 15% more than the internal volume of a standard 40-foot (12.2 meters) intermodal container:
A stack of standard 40-foot (12.2 meters) intermodal containers. Each container has an internal volume of about 68 cubic meters. Photograph by Martini171, available on Wikimedia under the CC BY-SA 3.0 Unported license.
answered Jan 25 at 17:18
AlexPAlexP
39.2k789153
$endgroup$
add a comment |
$begingroup$
For a back-of-the-envelope calculation the rule of thumb is that you need one cubic meter (1000 liters) of hydrogen or helium to lift one kilogram; so for 80 kilograms you need about 80 cubic meters (80,000 liters) of lifting gas.
For a more detailed calculation:
The average density of air at sea level is about 1.2 kg/m³.
The density of helium at 1 atmosphere pressure and 0°C temperature (that's called "standard temperature and pressure", STP) is about 0.18 kg/m³.
The lifting force is the difference between the weight of a volume of helium and the same volume of air, or 1.02 kg/m³.
For 80 kg you need 80 / 1.02 = 78.4 m³ of helium.
For a quick comparison, that's quite comparable with the capacity of a large railroad tank wagon, and about 15% more than the internal volume of a standard 40-foot (12.2 meters) intermodal container:
A stack of standard 40-foot (12.2 meters) intermodal containers. Each container has an internal volume of about 68 cubic meters. Photograph by Martini171, available on Wikimedia under the CC BY-SA 3.0 Unported license.
answered Jan 25 at 17:18
AlexPAlexP
39.2k789153
$endgroup$
add a comment |
$begingroup$
For a back-of-the-envelope calculation the rule of thumb is that you need one cubic meter (1000 liters) of hydrogen or helium to lift one kilogram; so for 80 kilograms you need about 80 cubic meters (80,000 liters) of lifting gas.
For a more detailed calculation:
The average density of air at sea level is about 1.2 kg/m³.
The density of helium at 1 atmosphere pressure and 0°C temperature (that's called "standard temperature and pressure", STP) is about 0.18 kg/m³.
The lifting force is the difference between the weight of a volume of helium and the same volume of air, or 1.02 kg/m³.
For 80 kg you need 80 / 1.02 = 78.4 m³ of helium.
For a quick comparison, that's quite comparable with the capacity of a large railroad tank wagon, and about 15% more than the internal volume of a standard 40-foot (12.2 meters) intermodal container:
A stack of standard 40-foot (12.2 meters) intermodal containers. Each container has an internal volume of about 68 cubic meters. Photograph by Martini171, available on Wikimedia under the CC BY-SA 3.0 Unported license.
answered Jan 25 at 17:18
AlexPAlexP
39.2k789153
$endgroup$
For a back-of-the-envelope calculation the rule of thumb is that you need one cubic meter (1000 liters) of hydrogen or helium to lift one kilogram; so for 80 kilograms you need about 80 cubic meters (80,000 liters) of lifting gas.
For a more detailed calculation:
The average density of air at sea level is about 1.2 kg/m³.
The density of helium at 1 atmosphere pressure and 0°C temperature (that's called "standard temperature and pressure", STP) is about 0.18 kg/m³.
The lifting force is the difference between the weight of a volume of helium and the same volume of air, or 1.02 kg/m³.
For 80 kg you need 80 / 1.02 = 78.4 m³ of helium.
For a quick comparison, that's quite comparable with the capacity of a large railroad tank wagon, and about 15% more than the internal volume of a standard 40-foot (12.2 meters) intermodal container:
A stack of standard 40-foot (12.2 meters) intermodal containers. Each container has an internal volume of about 68 cubic meters. Photograph by Martini171, available on Wikimedia under the CC BY-SA 3.0 Unported license.
answered Jan 25 at 17:18
AlexPAlexP
39.2k789153
edited Jan 25 at 22:06
answered Jan 25 at 17:18
AlexPAlexP
39.2k789153
answered Jan 25 at 17:18
AlexPAlexP
39.2k789153
answered Jan 25 at 17:18
AlexPAlexP
39.2k789153
39.2k789153
add a comment |
add a comment |
$begingroup$
I still doubt it would be able to fly if it had over 60kgs
Helium has a lifting force of one gram per liter. For a 60kg person or animal, you will therefore 60,000 liters. That is 15,850.323 gallons for americans.
The first thing that comes to my mind when I think about 60,000 liters is that it's the usual volume capacity for yhese trucks:
Also notice that flying this way may be very hard. Larry Walters comes to mind.
answered Jan 25 at 17:06
RenanRenan
49.5k13115248
$endgroup$
1
$begingroup$
Thatsalottahelium....
$endgroup$
– JBH
Jan 25 at 17:22
add a comment |
$begingroup$
I still doubt it would be able to fly if it had over 60kgs
Helium has a lifting force of one gram per liter. For a 60kg person or animal, you will therefore 60,000 liters. That is 15,850.323 gallons for americans.
The first thing that comes to my mind when I think about 60,000 liters is that it's the usual volume capacity for yhese trucks:
Also notice that flying this way may be very hard. Larry Walters comes to mind.
answered Jan 25 at 17:06
RenanRenan
49.5k13115248
$endgroup$
1
$begingroup$
Thatsalottahelium....
$endgroup$
– JBH
Jan 25 at 17:22
add a comment |
$begingroup$
I still doubt it would be able to fly if it had over 60kgs
Helium has a lifting force of one gram per liter. For a 60kg person or animal, you will therefore 60,000 liters. That is 15,850.323 gallons for americans.
The first thing that comes to my mind when I think about 60,000 liters is that it's the usual volume capacity for yhese trucks:
Also notice that flying this way may be very hard. Larry Walters comes to mind.
answered Jan 25 at 17:06
RenanRenan
49.5k13115248
$endgroup$
I still doubt it would be able to fly if it had over 60kgs
Helium has a lifting force of one gram per liter. For a 60kg person or animal, you will therefore 60,000 liters. That is 15,850.323 gallons for americans.
The first thing that comes to my mind when I think about 60,000 liters is that it's the usual volume capacity for yhese trucks:
Also notice that flying this way may be very hard. Larry Walters comes to mind.
answered Jan 25 at 17:06
RenanRenan
49.5k13115248
edited Jan 25 at 17:14
answered Jan 25 at 17:06
RenanRenan
49.5k13115248
answered Jan 25 at 17:06
RenanRenan
49.5k13115248
answered Jan 25 at 17:06
RenanRenan
49.5k13115248
49.5k13115248
1
$begingroup$
Thatsalottahelium....
$endgroup$
– JBH
Jan 25 at 17:22
add a comment |
1
$begingroup$
Thatsalottahelium....
$endgroup$
– JBH
Jan 25 at 17:22
1
1
$begingroup$
Thatsalottahelium....
$endgroup$
– JBH
Jan 25 at 17:22
$begingroup$
Thatsalottahelium....
$endgroup$
– JBH
Jan 25 at 17:22
add a comment |
$begingroup$
it would theoretically take 115920 cubic feet of helium to lig=ft 80 kilograms.
Because the difference in the up and downforce is 0.069 pounds. each cubic foot of helium could lift 0.069 pounds. In order to lift a single kilogram, you would need 1449 cubic feet of helium.
Now we have to transfer the cubic feet to liters.
1 cubic foot= 28 litres
115920x28
Theoretically, it would take 3245760 liters to lift 80 kilograms.
answered Jan 25 at 23:15
Rowyn AllowayRowyn Alloway
6321216
$endgroup$
add a comment |
$begingroup$
it would theoretically take 115920 cubic feet of helium to lig=ft 80 kilograms.
Because the difference in the up and downforce is 0.069 pounds. each cubic foot of helium could lift 0.069 pounds. In order to lift a single kilogram, you would need 1449 cubic feet of helium.
Now we have to transfer the cubic feet to liters.
1 cubic foot= 28 litres
115920x28
Theoretically, it would take 3245760 liters to lift 80 kilograms.
answered Jan 25 at 23:15
Rowyn AllowayRowyn Alloway
6321216
$endgroup$
add a comment |
$begingroup$
it would theoretically take 115920 cubic feet of helium to lig=ft 80 kilograms.
Because the difference in the up and downforce is 0.069 pounds. each cubic foot of helium could lift 0.069 pounds. In order to lift a single kilogram, you would need 1449 cubic feet of helium.
Now we have to transfer the cubic feet to liters.
1 cubic foot= 28 litres
115920x28
Theoretically, it would take 3245760 liters to lift 80 kilograms.
answered Jan 25 at 23:15
Rowyn AllowayRowyn Alloway
6321216
$endgroup$
it would theoretically take 115920 cubic feet of helium to lig=ft 80 kilograms.
Because the difference in the up and downforce is 0.069 pounds. each cubic foot of helium could lift 0.069 pounds. In order to lift a single kilogram, you would need 1449 cubic feet of helium.
Now we have to transfer the cubic feet to liters.
1 cubic foot= 28 litres
115920x28
Theoretically, it would take 3245760 liters to lift 80 kilograms.
answered Jan 25 at 23:15
Rowyn AllowayRowyn Alloway
6321216
answered Jan 25 at 23:15
Rowyn AllowayRowyn Alloway
6321216
answered Jan 25 at 23:15
Rowyn AllowayRowyn Alloway
6321216
answered Jan 25 at 23:15
Rowyn AllowayRowyn Alloway
6321216
6321216
add a comment |
add a comment |
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$begingroup$
Welcome to Worldbuilding! If you have a moment, please take the tour and visit the help center to learn more about the site. You may also find Worldbuilding Meta and The Sandbox useful. Here is a meta post on the culture and style of Worldbuilding.SE, just to help you understand our scope and methods, and how we do things here. Have fun!
$endgroup$
– Gryphon
Jan 25 at 17:06
5
$begingroup$
We know that there were flying dinosaurs weighting 145kg or more so there's no reason your dinosaur at 60 or 80kgs could not fly without using buoyancy.
$endgroup$
– Tim B♦
Jan 25 at 17:13
1
$begingroup$
@TimB pterosaurs are not dinosaurs, but that is a good low end mass estimate for Quetzalcoatlus. the largest flying dinosaur aka bird was around 70kg.
$endgroup$
– John
Jan 25 at 17:33
$begingroup$
There is a rather useful calculator here - omnicalculator.com/everyday-life/helium-balloons
$endgroup$
– chasly from UK
Jan 25 at 20:45
$begingroup$
This seems like a pure real-world physics question to me. Since we already have a site for those, I feel like this question should be migrated there.
$endgroup$
– Ilmari Karonen
Jan 25 at 21:11