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Why Do We Sleep Under Blankets, Even on the Hottest Nights? (2017)

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Re: Why Do We Sleep Under Blankets, Even on the Hottest Nights? (2017)

#11

Post by boelboel »

expedition32 wrote: post #3

I did not realize that things like sheets, blankets and pillows used to cost serious money.

Not just bedding but clothing was costly. High quality bedding (as well as clothing) still costs quite a bit of money especially once you take into account you need 2 sets for rotation. A proper quality set will run you $1000-2500 and there's luxury brands which will cost much more.

Re: Why Do We Sleep Under Blankets, Even on the Hottest Nights? (2017)

#12

Post by Ekaros »

out_of_protocol wrote: post #9
voidUpdate wrote: post #4

> "I barely know what a BTU is" Neither does anyone else, its one of those archaic units that changes slightly based on who is using it and hangs on in oil and gas industries, and also air conditioners and heaters. It was defined as the amount of energy to raise one pound of water by one degree Fahrenheit at one atmosphere of pressure, but that amount of energy depends on the starting temperature of the water, and di…

I blessed to live in a country that uses kilowatts. That works wonderfully (and advertised as such) for AC units

Kilowatts as in power consumption or as in refrigeration or heating power? AC is somewhat not straightforward.

Re: Why Do We Sleep Under Blankets, Even on the Hottest Nights? (2017)

#13

Post by ahmedfromtunis »

Is this a common thing? Sleeping without any sort of cover during the hot summer months (notably July and August) is the norm here (North Africa) and never heard of anyone who does it (AC or not).

Is this an American thing? Do people in warmer regions of the country (Texas, Florida, ...) also feel the same?

Re: Why Do We Sleep Under Blankets, Even on the Hottest Nights? (2017)

#14

Post by risingsubmarine »

'Go Wild' (John Ratey, Richard Manning) theorizes that the modern concept of bedrooms in which we segregate ourselves to sleep is a mismatch with our evolutionary established state. We would naturally lie in very close proximity of tribe and family for heat, contact and security. Sleeping and resting on one another out in the open. Perhaps pillows and blankets (esp weighted) serve as a proxy for this, not just temperature?

Re: Why Do We Sleep Under Blankets, Even on the Hottest Nights? (2017)

#15

Post by defrost »

bonsai_spool wrote: post #5
voidUpdate wrote: post #4

> "I barely know what a BTU is" Neither does anyone else, its one of those archaic units that changes slightly based on who is using it and hangs on in oil and gas industries, and also air conditioners and heaters. It was defined as the amount of energy to raise one pound of water by one degree Fahrenheit at one atmosphere of pressure, but that amount of energy depends on the starting temperature of the water, and di…

Why would the amount of energy required to increase the temperature of a defined mass of water depend on the temperature? This goes against the idea of specific heat (editing to add - I didn't realize that water's specific heat has a temperature dependence and changes around 5% over reasonable indoor temperatures https://www.engineeringtoolbox.com/specific-heat-capacity-wa... )

Traditionally it's not a "mass" of water, it's a pound (unqualified) of water.

There's an issue right there and one that cracks the door open to "how is pound of water created".

Leading into (depending on path to above) the issue of density of water, while famously and often described as incompressible, water reaches max density at 4 C, 3.99 degrees (Kelvin or Celsius) above water's triple point.

Re: Why Do We Sleep Under Blankets, Even on the Hottest Nights? (2017)

#17

Post by PowerElectronix »

bonsai_spool wrote: post #5
voidUpdate wrote: post #4

> "I barely know what a BTU is" Neither does anyone else, its one of those archaic units that changes slightly based on who is using it and hangs on in oil and gas industries, and also air conditioners and heaters. It was defined as the amount of energy to raise one pound of water by one degree Fahrenheit at one atmosphere of pressure, but that amount of energy depends on the starting temperature of the water, and di…

Why would the amount of energy required to increase the temperature of a defined mass of water depend on the temperature? This goes against the idea of specific heat (editing to add - I didn't realize that water's specific heat has a temperature dependence and changes around 5% over reasonable indoor temperatures https://www.engineeringtoolbox.com/specific-heat-capacity-wa... )

Specific heat usually varies with the temperature itself.

Re: Why Do We Sleep Under Blankets, Even on the Hottest Nights? (2017)

#18

Post by SupLockDef »

ahmedfromtunis wrote: post #13

Is this a common thing? Sleeping without any sort of cover during the hot summer months (notably July and August) is the norm here (North Africa) and never heard of anyone who does it (AC or not). Is this an American thing? Do people in warmer regions of the country (Texas, Florida, ...) also feel the same?

No, I often sleep on top of my bed during the hot summer days. I also don't put myself under the blankets when I take a nap.

I don't know what TFA is talking about.

Re: Why Do We Sleep Under Blankets, Even on the Hottest Nights? (2017)

#19

Post by bonsai_spool »

kgwgk wrote: post #10
bonsai_spool wrote: post #5

Earlier quoted context omitted.

Why would the amount of energy required to increase the temperature of a defined mass of water depend on the temperature? This goes against the idea of specific heat (editing to add - I didn't realize that water's specific heat has a temperature dependence and changes around 5% over reasonable indoor temperatures https://www.engineeringtoolbox.com/specific-heat-capacity-wa... )

No, it doesn't go against the idea of specific heat. You may be thinking of ideal gases and even then specific heat may or may not be constant: https://en.wikipedia.org/wiki/Perfect_gas

A specific heat is the amount of energy needed to raise a defined mass of a substance by a defined temperature.

What does that have to do with a perfect gas?

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