Homework Help: Physics

Posted by Jessica on Friday, October 8, 2010 at 7:50pm.

Consider 3 layers of a wall. The first layer is plaster 1.0 cm thick(R=0.033 SI units), the second layer is fiberglass insulation 8.9 cm thick (r=2.97), and the outside layer is woodd 3.0 cm thick(0.33). What is the heat loss through one square meter of wall if the inside temperature is 20 degress celcius and the outside is -10 degrees celcius

Physics - drwls, Friday, October 8, 2010 at 8:02pm
Thermal resistance is series can be added. The SI units are, presumably,
Watts/*m^2^*degC)

Total thermal resistance = 0.033 + 2.97 + 0.33 = 3.33 W/m^2*C

Multiply that by tha area (1 m^2) and 30 C for the heat loss rate in Watts.

It looks like 100 Watts.

For a large house, that will lead to a big heating bill in winter.

Answer this Question

Related Questions

physics - Consider three layers of a wall. The first layer is plaster 1.0 cm ...
physics - Animals in cold climates often depend on two layers of insulation: a ...
Math - A tabletop is made of two layers of plywood. The top layer is .584 inch ...
HEAT TRANSFER - Compute the heat flux thoroughly a 10 cm thick brick wall (k= 0....
OChem - A mixture of fluorene and benzoic acid is dissolved in diethyl ether and...
math - thomas wants to build a seven layer brick wall. the bottom layer has 20 ...
Math (Area of Shapes) - Suppose that the spool is 1m long and has an inner ...
math - a time capsule is in the shape of a cylinder with a hemisphere at each ...
maths - A brick wall is built by using 2 bricks less in each layer than in the ...
Physics - A ball moves at 33m/s through a wall of donuts 31 cm thick. It ...

For Further Reading

First Name:
School Subject:
Answer: