The latent heat of vaporization of h₂o at body temperature (37°c) is 2.42 x 10⁶ j/kg. to cool the body of a 60.4-kg jogger [average specific heat capacity = 3500 j/(kg c°)] by 1.08 c°, how many kilograms of water in the form of sweat have to be evaporated?

Explanation:

        Latent heat of vaporization of at 37°C is .

        When the sweat on our body evaporates, it absorbs energy from our body to overcome it's Latent heat of vaporisation. Thus our body cools down when sweat evaporates.

       So, Energy absorbed by sweat to evaporate = Energy lost by body

Specific heat capacity of human body = . Jogger weights 60.4 kg. Body temperature decreases by

       Energy absorbed from body =

∴ 0.094 kg of sweat has evaporated from the body.

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.

electrical power