Two identical thermometers, T1 T_1\,T1 and T2T_2T2, initially show the same room temperature reading. The bulb of thermometer T2 T_2\,T2 is wrapped in a piece of cotton soaked in water at room temperature, while the bulb of T1 T_1\,T1 is left dry. A fan is turned on to blow air at room temperature over both thermometers.
Which of the following statements correctly compares their readings and explains the underlying physical process?
T1T_1T1 shows a higher temperature than T2T_2T2 because the blowing air transfers thermal energy to T1T_1T1.
T1T_1T1 shows a higher temperature than T2T_2T2 because water evaporates from the wet cotton, absorbing latent heat and cooling T2T_2T2.
T2T_2T2 shows a higher temperature than T1T_1T1 because the wet cotton acts as an insulator, trapping heat in T2T_2T2.
T2T_2T2 shows a higher temperature than T1T_1T1 because the evaporation of water is an exothermic process that warms T2T_2T2.
528 exam-style questions on CIE IGCSE Physics 2.2 Thermal properties and temperature, covering 2.2.1 Thermal expansion of solids, liquids and gases, 2.2.2a Internal energy and temperature, 2.2.2b Specific heat capacity, 2.2.3a Melting, boiling, condensation and solidification, 2.2.3b Evaporation, and 2.2.3c Cooling by evaporation. Each one has a worked solution and a mark scheme showing where the marks go.