Suppose working outside on a hot day someone generate 450 J of heat each second.If this energy is compensated for by the evaporation of sweat,how much water would be lost in an hour? The latent heat of fusion for water is 334 kJ/kg and for vaporization is 2 200 kJ/kg.
A)4.9 liter
B)0.74 liter
C)0.50 liter
D)1.5 liter

Question

Quizplus · Accepted Answer

To find out how much water would be lost in an hour due to evaporation, we first calculate the total energy lost through sweat evaporation in an hour. Since 1 hour = 3600 seconds and the person generates 450 J of heat each second, the total energy is $450 \, \text{J/s} \times 3600 \, \text{s} = 1,620,000 \, \text{J} = 1620 \, \text{kJ}$.The latent heat of vaporization of water is given as $2200 \, \text{kJ/kg}$, which means $2200 \, \text{kJ}$ of energy is required to evaporate 1 kg (or 1 liter, since the density of water is approximately 1 kg/L) of water.To find the mass (or volume, in liters) of water evaporated, we use the formula:$$ \text{Mass of water evaporated} = \frac{\text{Total energy}}{\text{Latent heat of vaporization}} $$Substituting the given values:$$ \text{Mass of water evaporated} = \frac{1620 \, \text{kJ}}{2200 \, \text{kJ/kg}} = 0.736 \, \text{kg} $$Therefore, approximately 0.74 liters of water would be lost in an hour.

Suppose Working Outside on a Hot Day Someone Generate 450