Essential University Physics (3rd Edition)
3rd Edition
ISBN: 9780134202709
Author: Richard Wolfson
Publisher: PEARSON
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Chapter 16, Problem 85PP
Fiberglass is a popular, economical, and fairly effective building insulation. It consists of fine glass fibers—often including recycled glass—formed loosely into rectangular slabs or rolled into blankets (Fig. 16.18). One side is often faced with heavy paper or aluminum foil. Fiberglass insulation comes in thicknesses compatible with common building materials—for example, 3.5 inch and 6 inch for wood-framed walls. Standard 6-inch fiberglass has an R-factor of 19.
Fiberglass insulation for attics is available in 12-inch thickness. Its R-factor is
- a. 38.
- b. 76.
- c. 29.
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