How does a foam-filled winter coat help keep a person warm?

How does a foam-filled winter coat help keep a person warm?

• A. It slows down the transfer of thermal energy from outside to inside the coat.
• B. It slows down the transfer of thermal energy from inside to outside the coat.
• C. It speeds up the transfer of thermal energy from outside to inside the coat.
• D. It speeds up the transfer of thermal energy from inside to outside the coat.

Answer: (A)

Foam-filled insulation works by slowing the transfer of heat across the coat. The foam contains many tiny air pockets, and air is a poor conductor of heat. This makes the coat an effective barrier to heat flow, so thermal energy has a harder time moving from the outside environment into the coat and from your body out into the cold. The result is that your body heat stays inside more and the cold from outside doesn’t penetrate as quickly. In short, the insulation reduces heat transfer across the coat’s boundary, helping you feel warmer.

Foam-filled insulation works by slowing the transfer of heat across the coat. The foam contains many tiny air pockets, and air is a poor conductor of heat. This makes the coat an effective barrier to heat flow, so thermal energy has a harder time moving from the outside environment into the coat and from your body out into the cold. The result is that your body heat stays inside more and the cold from outside doesn’t penetrate as quickly. In short, the insulation reduces heat transfer across the coat’s boundary, helping you feel warmer.