Question

Explain how a light material, such as fiberglass insulation, makes an effective barrier to keep a home warm in the winter and cool in the summer.

a) The material traps air between the fibers. This reduces the amount of heat transfer between a home and the outside, because air has a low thermal conductivity. In addition, the air is trapped in small pockets which prevents convection, further reducing heat transfer.

b) The material's low density gives it a low mass for a fixed volume. In addition, its low density gives it a low specific heat. Thus the amount of heat transferred between a home and the outside is low because heat transfer is proportional to the mass and the specific heat of the material.

c) The material traps moisture in the air. Water has a high specific heat, which allows it to trap more heat for the same temperature difference. This effectively reduces the heat transfer between a home and the outside, because a lot of the heat is absorbed by the moisture in the material.

d) The material's low density means its emissivity is low. Since the amount of energy emitted in the form of radiation is proportional to the emissivity, the low density reduces the radiative heat transfer between a home and the environment.

Answer 1

Fiberglass insulation proves to be an effective barrier to keep home warm in winter and cool in summer by trapping air between the fibers , hence the amount of heat transferred between home and outside is significantly reduced resulting in low conductive insulation.

Correct option A