A person near a cold window on a windy day loses heat mainly through which modes?

A person near a cold window on a windy day loses heat mainly through which modes?

• A. Radiation and Conduction.
• B. Radiation and Convection.
• C. Conduction and Evaporation.
• D. Radiation and Evaporation.

Answer: (B)

Heat leaves the body mainly by radiation, convection, conduction, and evaporation. In this situation, the cold window provides a surface that is cooler than your body, so you lose heat by radiating toward the window. The windy conditions boost convective heat loss because moving air carries away the warm air near the skin, thinning the insulating boundary layer. Conduction through a solid or stationary air, and evaporation from moisture on the skin, are not the dominant pathways here. So the main modes are radiation to the cold window and convection with the moving air.

Heat leaves the body mainly by radiation, convection, conduction, and evaporation. In this situation, the cold window provides a surface that is cooler than your body, so you lose heat by radiating toward the window. The windy conditions boost convective heat loss because moving air carries away the warm air near the skin, thinning the insulating boundary layer. Conduction through a solid or stationary air, and evaporation from moisture on the skin, are not the dominant pathways here. So the main modes are radiation to the cold window and convection with the moving air.