English System Units and R value

In summary, Dan asked what unit the "h" represents in the R value for insulation in the English system units given by Serway. He clarified that it was not a homework question and expressed frustration with it being moved to the General Physics category. He also apologized for getting worked up about it.
  • #1
topsquark
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A quick units question. Serway gives the R value (for insulation) in English system units as:
[tex]\frac{ft^2 \, ^o F \, h}{BTU}[/tex]

What unit does "h" represent? Thanks!

-Dan
 
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  • #2
:grumpy: Alright, who moved it and why? I agree it's a "basic" question, but it is definitively NOT homework, which is why I put it in the General Physics category!

-Dan
 
  • #3
Hour. Long as there's a "pointer," who cares where it winds up --- let them fuss, and you get to be the adult --- you fuss and they fuss, and no one's an adult.
 
  • #4
Bystander said:
Hour. Long as there's a "pointer," who cares where it winds up --- let them fuss, and you get to be the adult --- you fuss and they fuss, and no one's an adult.

(Grumbles) It was too simple. (Sigh!) Thanks for telling me!

-Dan
 
  • #5
Bystander said:
Hour. Long as there's a "pointer," who cares where it winds up --- let them fuss, and you get to be the adult --- you fuss and they fuss, and no one's an adult.

Oh, I agree. I just get a little excitable every now and then! :rolleyes:

-Dan
 

1. What is the English system of units?

The English system of units is a system of measurement used primarily in the United States and other countries that were once part of the British Empire. It includes units such as inches, feet, yards, and miles for length; ounces, pounds, and tons for weight; and fluid ounces, pints, quarts, and gallons for volume.

2. How does the English system of units compare to the metric system?

The English system of units is often seen as less standardized and more complicated than the metric system. While the metric system is based on units of 10, the English system uses a variety of conversion factors (e.g. 12 inches in a foot, 16 ounces in a pound). This can make conversions between units more difficult.

3. What is the R value in the English system?

The R value, also known as the R-factor, is a measure of thermal resistance used in the English system. It is commonly used in the construction industry to rate the insulation properties of materials such as walls, floors, and ceilings. The higher the R value, the more resistant the material is to heat transfer.

4. How is the R value calculated?

The R value is calculated by dividing the thickness of the material (in inches) by its thermal conductivity (in British thermal units per hour per square foot per degree Fahrenheit). For example, a material that is 2 inches thick with a thermal conductivity of 0.5 would have an R value of 4 (2/0.5 = 4).

5. Why is the R value important?

The R value is important because it helps determine the energy efficiency of a building or structure. A higher R value means better insulation and can lead to lower energy costs and a more comfortable living or working environment. Building codes often require a minimum R value for different parts of a building, such as walls and roofs.

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