A very large swimming pool filled with water of temperture equal to `20^(@)`C is heated by a resistor with a heating power of 500 W for 20 minutes. Assuming the water in the pool is not in any contact with anything besides the resistor, determine the following quanties.
Is the change of entropy of the water positive, negative or zero?
`(i) DeltaS_("pool") gt 0 " " (ii) DeltaS_("pool")=0" "(iii) DeltaS_("pool") lt 0`

Answer

`DeltaS_("rev") =0`