Q4

Key Concept: Mechanism of Sweating

• Sweating is the body's primary method for regulating temperature through evaporation.

Conditions for Effective Cooling via Sweating

• For sweating to be an effective cooling mechanism, the following conditions must be met:

  • D. It must evaporate from the body.

  • This point emphasizes that the cooling effect is primarily due to the evaporation of sweat from the skin's surface. Without evaporation, the cooling process fails, and body temperature won't effectively reduce.

Incorrect Options Explained

• A. The relative humidity must be above 90\% .

  • High humidity conditions impede the evaporation of sweat, making it less effective as a cooling mechanism.

• B. Several layers of clothing must be worn.

  • More clothing can trap heat and moisture, hindering the evaporation process instead of facilitating cooling.

• C. The body must produce at least 1\text{ L} per hour.

  • Though sweat production can vary based on activity and temperature, this quantity is not a universal requirement for effective cooling, as even small amounts can be effective under appropriate conditions if evaporation occurs.